30 Pattern Program In C


In this article, you will learn to create 30 different Pattern program in C. Steps to create patterns are explained with the code.

  1. Square pattern in C
  2. Hollow square pattern
  3. Right triangle Pattern program in C
  4. Right Down triangle
  5. Left triangle Pattern program in C
  6. Left Down triangle
  7. Hollow triangle star pattern in C
  8. Pyramid star pattern in C
  9. Hollow pyramid star pattern in C
  10. Reverse pyramid star pattern in C
  11. Hourglass star pattern
  12. Diamond star pattern in C
  13. Hollow Diamond star pattern in C
  14. Right Pascal star pattern
  15. Left Pascal star pattern
  16. Plus star pattern
  17. Cross star pattern
  18. Heart star pattern
  19. Right triangle number pattern
  20. Left triangle number pattern
  21. Number pyramid pattern
  22. Hollow number pyramid pattern
  23. Number pyramid reverse pattern
  24. Number diamond pattern
  25. Hollow number diamond pattern
  26. Alphabet diamond pattern
  27. Hollow alphabet diamond pattern
  28. Alphabet pyramid pattern
  29. Hollow alphabet pyramid pattern
  30. Reverse alphabet pyramid pattern

Pattern program in C

1. Square pattern in C

The simplest pattern you can draw using C is a square pattern. It has a shape of a square or rectangle.

*****
*****
*****
*****
*****

Follow these simple steps to create the square pattern in C:

  1. Take the size of the square or take user input.
  2. Create a nested loop where the external loop prints rows and the inner loop prints each star in the column.

  3. Print the stars using the command printf("*").
#include <stdio.h>

int main() {
  // take a size
  // you can take user input
  int size = 5;
  // external loop
  for (int i = 0; i < size; i++) {
    // internal loop
    for (int j = 0; j < size; j++) {
      printf("*");
    }
    printf("\n");
  }
  return 0;
}

Output:

*****
*****
*****
*****
*****

2. Hollow Square pattern in C

hollow square is a variation of square pattern. It has a similar shape but is hollow inside.

*****
*   *
*   *
*   *
*****

Steps to create a hollow square pattern in C are as follows:

  1. Start with the size of the square.
  2. Create a nested loop. Here the inner loop is a bit complex.
  3. If the row is first or last print only star.
  4. If the row is not first or last then print star at first and last position of row and space at the middle position.
  5. Create a new line at the end of each row.
#include <stdio.h>

int main() {
  // size of the square
  int size = 5;
  // external loop
  for (int i = 0; i < size; i++) {
    // innternal loop
    for (int j = 0; j < size; j++) {
      // in first and last row print only stars
      if (i == 0 || i == size - 1) {
        printf("*");
      }
      else {
        // at first and last position
        // of row print stars else print spaces
        if (j == 0 || j == size - 1) {
          printf("*");
        }
        else {
          printf(" ");
        }
      }
    }
    printf("\n");
  }
  return 0;
}

Output:

*****
*   *
*   *
*   *
*****

3. Right triangle pattern program in C

The right triangle star pattern in C is a right angle triangle that has its perpendicular line at the right side of the triangle.

    *
   **
  ***
 ****
*****

You can see the pattern above. Before printing stars, we have to print spaces in a certain pattern to push stars to the right side of the triangle.

Follow the steps below to create the right triangle star pattern in C:

  1. Start with creating an external loop with 2 inner loops, 1st to print spaces and 2nd to print stars.
  2. In the 1st inner loop start printing spaces for the size minus row number.
  3. In the 2nd inner loop start printing stars for the row number.
  4. At the end of both inner loops print a new line.
#include <stdio.h>

int main() {
  // set size
  // or take user input
  int size = 5;

  for (int i = 0; i < size; i++) {
    // printing spaces before stars
    for (int j = 1; j < size-i; j++) {
      printf(" ");
    }
    // printing stars
    for (int k = 0; k <= i; k++) {
      printf("*");
    }
    printf("\n");
  }
  return 0;
}

Output:

    *
   **
  ***
 ****
*****

4. Right Down Triangle

The right down triangle is another triangle pattern which is a water image of a right triangle.

*****
 ****
  ***
   **
    *

You can see the pattern above. It is very much the same as the right triangle star pattern with just little modifications in the code. Here is the complete code for this.

#include <stdio.h>

int main() {
  // take size
  int size = 5;

  for (int i = 0; i < size; i++) {
    // printing spaces
    for (int j = 0; j < i; j++) {
      printf(" ");
    }
    // printing stars
    for (int j = size; j > i; j--) {
      printf("*");
    }
    printf("\n");
  }
  return 0;
}

Output:

*****
 ****
  ***
   **
    *

5. Left triangle star pattern in C

The left triangle star pattern is a triangle with a perpendicular line at the left side of the triangle.

*
**
***
****
*****

Follow the steps below to create the left triangle star pattern in C:

  1. Take the size of the triangle.
  2. Start with creating a nested loop where the inner loop prints the star a number of times as the row number.
  3. At the end of each row print new line by print("\n").
#include <stdio.h>

int main() {
  // take size of triangle
  int size = 5;
  
  for (int i = 0; i < size; i++) {
    // printing star in a row
    for (int j = 0; j <= i; j++) {
      printf("*");
    }
    printf("\n");
  }
  return 0;
}

Output:

*
**
***
****
*****

6. Left Down Triangle

The left down triangle is a variation of the left triangle star pattern. It is a water image of this pattern.

*****
****
***
**
*

With just a little modification in code, you can reverse the order of printing stars and spaces and create this pattern. Here is the complete code for this.

#include <stdio.h>

int main() {
  // size of the triangle
  int size = 5;

  for (int i = 0; i < size; i++) {
    // printing stars
    for (int j = 0; j < size-i; j++) {
      printf("*");
    }
    printf("\n");
  }
  return 0;
}

Output:

*****
****
***
**
*

7. Hollow triangle star pattern in C

The hollow triangle star pattern is a little complex structure of a triangle. It is a triangle with a hollow space in the middle.

*
**
* *
*  *
*   *
******

You can see the pattern above. You have to manage the spaces and stars in a certain way to create this pattern.

  1. Set the size of your triangle.
  2. Use nested loops where the external loop handles rows and the internal loop handles each column of the row.
  3. In the internal loop check if it's not the last row and is 1st and last position of the row then print star, else print space.
  4. In the last row print only stars.
#include <stdio.h>

int main() {

  int size = 5;

  // creating hollow triangle
  for (int i = 1; i <= size; i++) {
    for (int j = 0; j < i; j++) {
      // operation of non-last row
      if (i != size) {
        // 1st or last position of row print star
        if (j == 0 || j == i-1) {
          printf("*");
        } else {
          printf(" ");
        }
      }
      // last row print only star
      else {
        printf("*");
      }
    }
    printf("\n");
  }
  return 0;
}

Output:

*
**
* *
*  *
*   *
******

8. Pyramid star pattern in C

The pyramid pattern in C is a very famous pattern shape that looks like an equilateral triangle.

    *
   ***
  *****
 *******
*********

The complete step to create a pyramid star pattern in C is given below:

  1. Take the size of the pyramid as input or a fixed number (here 5).
  2. Create an external loop with 2 internal loops inside. 1st loop prints spaces and 2nd loop prints stars.
  3. Print spaces for a number of times as size minus row number.
  4. Print stars for 2 times as row number minus 1.
  5. Break the line after each row.
#include <stdio.h>

int main() {
  int size = 5;

  // creating pyramid
  for (int i = 0; i < size; i++) {
    // print spaces before stars
    for (int j = 0; j < size-i-1; j++) {
      printf(" ");
    }
    // print stars
    for (int k = 0; k < 2*i+1; k++) {
      printf("*");
    }
    printf("\n");
  }
  return 0;
}

Output:

    *
   ***
  *****
 *******
*********

Stay Ahead, Learn More


9. Hollow pyramid pattern program in C

The hollow pyramid is a normal pyramid but with a hollow space in the middle.

    *
   * *
  *   *
 *     *
*********

You can see the pattern above. This is a bit complicated to create this pattern. Here are steps to follow:

  1. Create a nested loop with 2 internal loops to print spaces and stars.
  2. In the first loop print only spaces for a number of times as size minus row number.
  3. The functioning of the second loop is quite complex. In this loop check if it is the first or the last row then only print stars. If it is another row then check if it is 1st and last position of the row then print star, else print space.
  4. Break the line after 2nd internal loop.
#include <stdio.h>

int main() {
  // size of the pyramid
  int size = 5;
  for (int  i = 0; i < size; i++) {
    // print spaces
    for (int j = 0; j < size-i-1; j++) {
      printf(" ");
    }
    // print stars
    for (int k = 0; k < 2*i+1; k++) {
      if(k == 0 || k == 2*i || i == size-1) {
        printf("*");
      } else {
        printf(" ");
      }
    }
    printf("\n");
  }
  return 0;
}

Output:

    *
   * *
  *   *
 *     *
*********

10. Reverse pyramid star pattern in C

The reverse pyramid star pattern in C is another version of the pyramid star pattern that has nothing but the 180-degree rotation of the pyramid star pattern.

*********
 *******
  *****
   ***
    *

Here is the complete code to create a reverse pyramid pattern in C.

#include <stdio.h>

int main() {
  // size of the pyramid
  int size = 5;
  for (int i = 0; i < size; i++) {
    // print spaces
    for (int j = 0; j < i; j++) {
      printf(" ");
    }
    // print stars
    for (int k = 0; k < 2*(size-i)-1; k++) {
      printf("*");
    }
    printf("\n");
  }
  return 0;
}

Output:

*********
 *******
  *****
   ***
    *

11. Hourglass star pattern in C

The hourglass pattern is a pattern having a shape like an hourglass. It is a combination of a pyramid and a hollow pyramid.

*********
 *******
  *****
   ***
    *
   ***
  *****
 *******
*********

Here is the complete code to create an hourglass pattern in C.

#include <stdio.h>

int main() {
  int size = 5;
  // reversed pyramid star pattern
  for (int i = 0; i < size; i++) {
    // printing spaces
    for (int j = 0; j < i; j++) {
      printf(" ");
    }
    // printing star
    for (int k = 0; k < (size-i)*2-1; k++) {
      printf("*");
    }
    printf("\n");
  }
  // pyramid star pattern
  for (int i = 2; i <= size; i++) {
    // printing spaces
    for (int j = size; j > i; j--) {
      printf(" ");
    }
    // printing star
    for (int k = 0; k < i*2-1; k++) {
      printf("*");
    }
    printf("\n");
  }
  return 0;
}

Output:

*********
 *******
  *****
   ***
    *
   ***
  *****
 *******
*********

12. Diamond star pattern in C

Shown below is the diamond star pattern. It is a mixture of the pyramid and reverses the pyramid star patterns.

    *
   ***
  *****
 *******
*********
 *******
  *****
   ***
    *

Here is the complete code to create a diamond star pattern in C.

#include <stdio.h>

int main() {
  int size = 5;
  // upside pyramid
  for (int i = 1; i <= size; i++) {
    // printing spaces
    for (int j = size; j > i; j--) {
      printf(" ");
    }
    // printing star
    for (int k = 0; k < i*2-1; k++) {
      printf("*");
    }
    printf("\n");
  }
  // downside pyramid
  for (int i = 1; i <= size-1; i++) {
    // printing spaces
    for (int j = 0; j < i; j++) {
      printf(" ");
    }
    // printing star
    for (int k = (size-i)*2-1; k > 0; k--) {
      printf("*");
    }
    printf("\n");
  }
  return 0;
}

Output:

    *
   ***
  *****
 *******
*********
 *******
  *****
   ***
    *

13. Hollow diamond star pattern in C

The hollow diamond pattern is a simple diamond pattern with stars only at the boundary.

    *
   * *
  *   *
 *     *
*       *
 *     *
  *   *
   * *
    *

Here is the complete code to create a hollow diamond star pattern in C.

#include <stdio.h>

int main() {
  int size = 5;
  // upside pyramid
  for (int i = 1; i <= size; i++) {
    // printing spaces
    for (int j = size; j > i; j--) {
      printf(" ");
    }
    // printing star
    for (int k = 0; k < i*2-1; k++) {
      if (k == 0 || k == 2*i-2) {
        printf("*");
      }
      else {
        printf(" ");
      }
    }
    printf("\n");
  }
  // downside triangle
  for (int i = 1; i < size; i++) {
    // printing spaces
    for (int j = 0; j < i; j++) {
      printf(" ");
    }
    // printing star
    for (int k = (size-i)*2-1; k >= 1; k--) {
      if (k == 1 || k == (size-i)*2-1) {
        printf("*");
      }
      else {
        printf(" ");
      }
    }
    printf("\n");
  }
  return 0;
}

Output:

    *
   * *
  *   *
 *     *
*       *
 *     *
  *   *
   * *
    *

14. Right pascal star pattern

Shown below is the right pascal star pattern.

*
**
***
****
*****
****
***
**
*

You can see the pattern above it is a mixture of the left triangle and reverse left triangle. The complete code of the right pascal star pattern in C is given below.

#include <stdio.h>

int main() {
  // right pasal triangle
  int size = 5;

  for (int i = 1; i <= size; i++) {
    for (int j = 0; j < i; j++) {
      printf("*");
    }
    printf("\n");
  }
  
  for (int i = 1; i <= size-1; i++) {
    for (int j = 0; j < size-i; j++) {
      printf("*");
    }
    printf("\n");
  }
  return 0;
}

Output:

*
**
***
****
*****
****
***
**
*

15. Left pascal star pattern

    *
   **
  ***
 ****
*****
 ****
  ***
   **
    *

The above pattern is the left pascal star pattern. Code to create this is given below.

#include <stdio.h>

int main() {
  // left pasal triangle
  int size = 5;

  for (int i = 1; i <= size; i++) {
    for (int j = 0; j < size-i; j++) {
      printf(" ");
    }
    for (int k = 0; k < i; k++) {
      printf("*");
    }
    printf("\n");
  }
  for (int i = 1; i <= size-1; i++) {
    for (int j = 0; j < i; j++) {
      printf(" ");
    }
    for (int k = 0; k < size-i; k++) {
      printf("*");
    }
    printf("\n");
  }
  return 0;
}

Output:

    *
   **
  ***
 ****
*****
 ****
  ***
   **
    *

16. Plus pattern program in C

plus pattern has a shape of the mathematical plus sign(+).

  *
  *
*****
  *
  *

The code to create plus pattern in C is given below.

#include <stdio.h>

int main() {
  // size of plus, use odd number
  int size = 5;

  for (int i = 0; i < size; i++) {
    for (int j = 0; j < size; j++) {
      // print only stars in middle row
      if (i == size / 2) {
        printf("*");
      }
      // other than middle row, print star only at index size/2
      else {
        if (j == size / 2) {
          printf("*");
        } else {
          printf(" ");
        }
      }
    }
    printf("\n");
  }
  return 0;
}

Output:

  *
  *
*****
  *
  *

17. Cross pattern program in C

The cross pattern has the shape of the mathematical cross sign(x).

*   *
 * * 
  *  
 * * 
*   *

The code to create cross pattern in C is given below.

#include <stdio.h>

int main() {
  // size of cross, use odd number
  int size = 5;

  for (int i = 0; i < size; i++) {
    for (int j = 0; j < size; j++) {
      if (i==j || i+j==size-1) {
        printf("*");
      } else {
        printf(" ");
      }
    }
    printf("\n");
  }
  return 0;
}

Output:

*   *
 * *
  *
 * *
*   *

18. Heart pattern

 ***   ***
***** *****
***********
 *********
  *******
   *****
    ***
     *

The Heart star pattern in C is quite complex structure. The code to create this is given below.

#include <stdio.h>

int main() {
  // heart star pattern
  int size = 6;

  for (int i = size / 2; i < size; i += 2) {
    // print first spaces
    for (int j = 1; j < size-i; j += 2) {
      printf(" ");
    }
    // print first stars
    for (int j = 1; j < i+1; j++) {
      printf("*");
    }
    // print second spaces
    for (int j = 1; j < size-i+1; j++) {
      printf(" ");
    }
    // print second stars
    for (int j = 1; j < i+1; j++) {
      printf("*");
    }
    printf("\n");
  }
  // lower part
  // inverted pyramid
  for (int i = size; i > 0; i--) {
    for (int j = 0; j < size-i; j++) {
      printf(" ");
    }
    for (int j = 1; j < i*2; j++) {
      printf("*");
    }
    printf("\n");
  }
  return 0;
}

Output:

 ***   ***
***** *****
***********
 *********
  *******
   *****
    ***
     *

Above we have covered 18 different star pattern in C now let's look at some number patterns.

19. Right triangle number pattern

    1
   12
  123
 1234
12345

You can see above right triangle number pattern. The code to create this is given below.

#include <stdio.h>

int main() {

  int size = 5;
  // loop to print the pattern
  for (int i = 0; i < size; i++) {
    // print spaces
    for (int j = 1; j < size-i; j++) {
      printf(" ");
    }
    // print number
    for (int k = 0; k <= i; k++) {
      printf("%d", (k+1));
    }
    printf("\n");
  }
  return 0;
}

Output:

    1
   12
  123
 1234
12345

20. Left triangle number pattern

1
12
123
1234
12345

You can see above left triangle number pattern. The code to create this is given below.

#include <stdio.h>

int main() {

  int size = 5;
  // loop to print the pattern
  for (int i = 0; i < size; i++) {
    // print column
    for (int j = 0; j <= i; j++) {
      printf("%d", (j+1));
    }
    printf("\n");
  }
  return 0;
}

Output:

1
12
123
1234
12345

21. Number pyramid pattern

The number pyramid pattern has the shape of the pyramid that is made up of numbers.

    1
   123
  12345
 1234567
123456789

Here is pyramid pattern programs using numbers using C in detail. The code to create this is given below.

#include <stdio.h>

int main() {

  int size = 5;
  for (int i = 0; i < size; i++) {
    // print spaces
    for (int j = 0; j < size-i-1; j++) {
      printf(" ");
    }
    // print number
    for (int k = 0; k < 2*i+1; k++) {
      printf("%d", k+1);
    }
    printf("\n");
  }
  return 0;
}

Output:

    1
   123
  12345
 1234567
123456789

22. Hollow number pyramid pattern

The hollow number pyramid pattern is a normal number pyramid with numbers only at boundaries.

    1
   1 2
  1   2
 1     2
123456789

The code to create a hollow number pyramid pattern is given below.

#include <stdio.h>

int main() {

  int size = 5;
  for (int i = 0; i < size; i++) {
    // print spaces
    for (int j = 0; j < size-i-1; j++) {
      printf(" ");
    }
    // print number
    int num = 1;
    for (int k = 0; k < 2*i+1; k++) {
      if (i == 0 || i == size-1) {
        printf("%d", num++);
      } else {
        if (k == 0 || k == 2*i) {
          printf("%d", num++);
        } else {
          printf(" ");
        }
      }
    }
    printf("\n");
  }
  return 0;
}

Output:

    1
   1 2
  1   2
 1     2
123456789

23. Number pyramid reverse pattern

The reverse number pyramid pattern is a number pyramid pattern rotated 180 degrees.

123456789
 1234567
  12345
   123
    1

The code to create a reverse number pyramid pattern in C is given below.

#include <stdio.h>

int main() {

  int size = 5;
  for (int i = 0; i < size; i++) {
    // print spaces
    for (int j = 0; j < i; j++) {
      printf(" ");
    }
    // print number
    for (int k = 0; k < 2*(size-i)-1; k++) {
      printf("%d", k+1);
    }
    printf("\n");
  }
  return 0;
}

Output:

123456789
 1234567
  12345
   123
    1

24. Number diamond pattern

The number diamond pattern is the same as the diamond pattern we have seen above but this one is just made of numbers.

    1
   123
  12345
 1234567
123456789
 1234567
  12345
   123
    1

The code to create a number diamond pattern in C is given below.

#include <stdio.h>

int main() {
  int size = 5;
  int num = 1;
  // upside pyramid
  for (int i = 1; i <= size; i++) {
    // printing spaces
    for (int j = size; j > i; j--) {
      printf(" ");
    }
    // printing number
    for (int k = 0; k < i*2-1; k++) {
      printf("%d", num++);
    }
    // set the number to 1
    num = 1;
    printf("\n");
  }
  // downside pyramid
  for (int i = 1; i <= size-1; i++) {
    // printing spaces
    for (int j = 0; j < i; j++) {
      printf(" ");
    }
    // printing number
    for (int k = (size-i)*2-1; k > 0; k--) {
      printf("%d", num++);
    }
    // set num to 1
    num = 1;
    printf("\n");
  }
  return 0;
}

Output:

    1
   123
  12345
 1234567
123456789
 1234567
  12345
   123
    1

25. Hollow number diamond pattern

The hollow number diamond pattern is hollow diamond pattern made up of numbers.

    1
   1 2
  1   2
 1     2
1       2
 1     2
  1   2
   1 2
    1

The code to create hollow number diamond pattern in C is given below.

#include <stdio.h>

int main() {
  int size = 5, num = 1;
  // upside pyramid
  for (int i = 1; i <= size; i++) {
    // printing spaces
    for (int j = size; j > i; j--) {
      printf(" ");
    }
    // printing number
    for (int k = 0; k < i*2-1; k++) {
      if (k == 0 || k == 2*i-2) {
        printf("%d", num++);
      } else {
        printf(" ");
      }
    }
    // set the number to 1
    num = 1;
    printf("\n");
  }
  // downside triangle
  for (int i = 1; i < size; i++) {
    // printing spaces
    for (int j = 0; j < i; j++) {
      printf(" ");
    }
    // printing number
    for (int k = (size-i)*2-1; k >= 1; k--) {
      if (k == 1 || k == (size-i)*2-1) {
        printf("%d", num++);
      } else {
        printf(" ");
      }
    }
    // set the number to 1
    num = 1;
    printf("\n");
  }
  return 0;
}

Output:

    1
   1 2
  1   2
 1     2
1       2
 1     2
  1   2
   1 2
    1

LNow look at some alphabet pattern in C.

26. Alphabet diamond pattern

The alphabet diamond pattern is normal diamond pattern made up of alphabet.

    A
   ABC
  ABCDE
 ABCDEFG
ABCDEFGHI
 ABCDEFG
  ABCDE
   ABC
    A

To print character in C use printf("%c", ch) .The complete code for the alphabet diamond pattern program in C is given below.

#include <stdio.h>

int main() {
  int size = 5;
  int alpha = 65;
  int num = 0;
  // upside pyramid
  for (int i = 1; i <= size; i++) {
    // printing spaces
    for (int j = size; j > i; j--) {
      printf(" ");
    }
    // printing alphabets
    for (int k = 0; k < i*2-1; k++) {
      printf("%c", alpha + num++);
    }
    // set the number to 0
    num = 0;
    printf("\n");
  }
  // downside pyramid
  for (int i = 1; i <= size-1; i++) {
    // printing spaces
    for (int j = 0; j < i; j++) {
      printf(" ");
    }
    // printing alphabets
    for (int k = (size-i)*2-1; k > 0; k--) {
      printf("%c", alpha + num++);
    }
    // set num to 0
    num = 0;
    printf("\n");
  }
  return 0;
}

Output:

    A
   ABC
  ABCDE
 ABCDEFG
ABCDEFGHI
 ABCDEFG
  ABCDE
   ABC
    A

27. Hollow alphabet diamond pattern

The hollow alphabet diamond pattern is shown below.

    A
   A B
  A   B
 A     B
A       B
 A     B
  A   B
   A B
    A

The code to create hollow alphabet diamond pattern in C is given below.

#include <stdio.h>

int main() {
  int size = 5;
  int alpha = 65;
  int num = 0;
  // upside pyramid
  for (int i = 1; i <= size; i++) {
    // printing spaces
    for (int j = size; j > i; j--) {
      printf(" ");
    }
    // printing alphabets
    for (int k = 0; k < i*2-1; k++) {
      if (k == 0 || k == 2*i-2) {
        printf("%c", alpha + num++);
      } else {
        printf(" ");
      }
    }
    // set the number to 0
    num = 0;
    printf("\n");
  }
  // downside triangle
  for (int i = 1; i < size; i++) {
    // printing spaces
    for (int j = 0; j < i; j++) {
      printf(" ");
    }
    // printing alphabets
    for (int k = (size-i)*2-1; k >= 1; k--) {
      if (k == 1 || k == (size-i)*2-1) {
        printf("%c", alpha + num++);
      } else {
        printf(" ");
      }
    }
    // set the number to 0
    num = 0;
    printf("\n");
  }
  return 0;
}

Output:

    A
   A B
  A   B
 A     B
A       B
 A     B
  A   B
   A B
    A

28. Alphabet pyramid pattern

The alphabet pyramid pattern is a normal pyramid pattern made up of the alphabet.

    A
   ABC
  ABCDE
 ABCDEFG
ABCDEFGHI

The code to create alphabet pyramid pattern in C is given below.

#include <stdio.h>

int main() {

  int size = 5, alpha = 65;
  for (int i = 0; i < size; i++) {
    // print spaces
    for (int j = 0; j < size-i-1; j++) {
      printf(" ");
    }
    // print alphabets
    for (int k = 0; k < 2*i+1; k++) {
      printf("%c", alpha+k);
    }
    printf("\n");
  }
  return 0;
}

Output:

    A
   ABC
  ABCDE
 ABCDEFG
ABCDEFGHI

29. Hollow alphabet pyramid pattern

Here is how hollow alphabet pyramid pattern looks like.

    A
   B C
  D   E
 F     G
HIJKLMNOP

The code to create hollow alphabet pyramid pattern in C is given below.

#include <stdio.h>

int main() {
  
  int size = 5, alpha = 65, num = 0;
  for (int i = 0; i < size; i++) {
    // print spaces
    for (int j = 0; j < size-i-1; j++) {
      printf(" ");
    }
    // print alphabets
    for (int k = 0; k < 2*i+1; k++) {
      if (i == 0 || i == size - 1) {
        printf("%c", alpha + num++);
      } else {
        if (k == 0 || k == 2*i) {
          printf("%c", alpha + num++);
        } else {
          printf(" ");
        }
      }
    }
    printf("\n");
  }
  return 0;
}

Output:

    A
   B C
  D   E
 F     G
HIJKLMNOP

30. Reverse alphabet pyramid pattern

The reverse alphabet pyramid pattern is alphabet pattern in reverse order.

ABCDEFGHI
 ABCDEFG
  ABCDE
   ABC
    A

The code to create reverse alphabet pyramid pattern in C is given below.

#include <stdio.h>

int main() {
  // size of the square
  int size = 5, alpha = 65;
  for (int i = 0; i < size; i++) {
    // print spaces
    for (int j = 0; j < i; j++) {
      printf(" ");
    }
    // print alphabets
    for (int k = 0; k < 2*(size-i)-1; k++) {
      printf("%c", alpha + k);
    }
    printf("\n");
  }
  return 0;
}

Output:

ABCDEFGHI
 ABCDEFG
  ABCDE
   ABC
    A

Conclusion

In this article, we have covered 30 different pattern programs in C of different variations like stars, numbers, and alphabets.

Check out other pattern programs in different programming languages. pattern program in C++, star pattern in javascript, pattern program in python, and pattern program in java.