C Program To Print Pyramid Pattern Of Numbers

In this article, you will look at C program to print pyramid pattern of numbers. We will see different types of pyramids like hollow pyramids, reverse pyramids, etc.

Table Of Contents

Number pyramid pattern in C
1. Pyramid - Number increment in row
2. Pyramid - Number increment in column
Reverse Number pyramid pattern in C
1. Reverse pyramid - Number increment in row
2. Reverse pyramid - Number increment in column
Hollow Number pyramid
Hollow reverse pyramid

C program to print pyramid pattern of numbers

1. Number pyramid pattern in C

Number pyramid pattern in C is a very famous pyramid pattern made up of numbers and has the shape of an equilateral triangle which is called a pyramid in this sense.

These patterns can be created with different kinds of arrangements of numbers. We will see 2 types here. In one types number increase in a row and in other types number increase in the column.

1.1. Pyramid - Number increment in row

In this pattern, the number starts from 1 in each row and increases throughout the row. And from next line again starts from 1. Here is how it looks.

Here are the steps to create this pattern.

Take variable 'size' to store the size of the pyramid.
Set it a value either by user input or default value.
Create a for loop to print pyramid and execute it for 'size' number of times.
Inside this loop create 2 other loops first one to print spaces and the second one to print numbers.
Print spaces for size of pyramid minus current row number.
Print numbers for 2 * current row number + 1. Use row variable to print increasing numbers.
Print new line after each row.

#include <stdio.h>

int main() {
  // size of pyramid
  // can also be read from stdin
  int size = 5;
  for (int i = 0; i < size; i++) {
    // printing spaces
    for (int j = 0; j < size-i-1; j++) {
      printf(" ");
    }
    // printing number
    for (int k = 0; k < 2*i+1; k++) {
      printf("%d", k+1);
    }
    printf("\n");
  }
  return 0;
}

Output:

1.2. Pyramid - Number increment in column

In this pattern number starts from 1 in the first row, in second-row number will be 2 and the same numbers will be printed throughout the row. Here is how it looks.

Steps to create this are almost the same as above but in step number 6 use the external variable 'i' to print numbers. This will cause printing the same number throughout the row and number increase only in the next row.

#include <stdio.h>

int main() {
  // size of pyramid
  // can also be read from stdin
  int size = 5;
  for (int i = 0; i < size; i++) {
    // printing spaces
    for (int j = 0; j < size-i-1; j++) {
      printf(" ");
    }
    // printing numbers
    for (int k = 0; k < 2*i+1; k++) {
      printf("%d", i+1);
    }
    printf("\n");
  }
  return 0;
}

Output:

2. Reverse Number pyramid pattern in C

The reverse number pyramid is a pyramid pattern just rotated 180 degrees. You can also visualize it as a water image of a number pyramid.

Again it can have 2 types. One type has an increasing number in a row and another type has an increasing number in the column.

2.1. Reverse pyramid - Number increment in row

This is a reverse number pyramid pattern where numbers start from 1 in each row and increase throughout the row. Here is how it looks.

The steps to create a reverse number pyramid is as follows:

Take the size of your pyramid.
Create a nested loop to print the pyramid.
In the first internal loop print spaces for current row number minus 1.
In the second internal loop print numbers for 2 times of size minus current row number and minus 1.
Print newline after end of the second internal loop.

#include <stdio.h>

int main() {
  // size of pyramid
  // can also take user input
  int size = 5;
  for (int i = 0; i < size; i++) {
    // printing 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:

2.2. Reverse pyramid - Number increment in column

This is a reverse number pyramid pattern and numbers start from 1 in the first row, 2 in the second row and so on. Here is how it looks.

This is the same as the above program just change the number printing variable to 'i' and you will have this pattern.

#include <stdio.h>

int main() {
  // size of pyramid
  // can also take user input
  int size = 5;
  for (int i = 0; i < size; i++) {
    // printing spaces
    for (int j = 0; j < i; j++) {
      printf(" ");
    }
    // print number
    for (int k = 0; k < 2*(size-i)-1; k++) {
      printf("%d", i+1);
    }
    printf("\n");
  }
  return 0;
}

Output:

3. Hollow number pyramid pattern

The hollow number pyramid pattern is a pyramid pattern that has a number only at boundaries and is hollow inside.

The complete code for the hollow number pyramid pattern program in C is as follows:

#include <stdio.h>

int main() {
  // size of pyramid
  // can also take user input
  int size = 5;
  for (int i = 0; i < size; i++) {
    // printing spaces
    for (int j = 0; j < size-i-1; j++) {
      printf(" ");
    }
    // printing number and inner spaces
    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:

4. Hollow reverse number pyramid pattern

The hollow reverse number pyramid pattern is a pyramid pattern that is reversed as well as hollo inside.

The code of hollow reversed number pyramid is very much like a normal hollow pyramid pattern, with just a little change in the code.

#include <stdio.h>

int main() {
  // size of pyramid
  // can also take user input
  int size = 5;
  for (int i = 0; i < size; i++) {
    // printing spaces
    // in order 1, 2 , 3,...
    for (int j = 0; j < i; j++) {
      printf(" ");
    }
    // printing number and inner spaces
    int num = 1;
    for (int k = 0; k < 2*(size-i)-1; k++) {
      // print number in 1st and last row
      if (i == 0 || i == size - 1) {
        printf("%d", num++);
      } else {
        // print number at 1st and last position of other rows
        if (k == 0 || k == 2*(size-i-1)) {
          printf("%d", num++);
        } else {
          printf(" ");
        }
      }
    }
    printf("\n");
  }
  return 0;
}

Output:

Conclusion

In this short guide, we have seen 6 different C program to print pyramid pattern of numbers. Here is the list of other pattern programs in C that you must have a look at.

If you want to check more pattern programs in another programming language than C then look at star pattern in javascript, pattern program in python, star pattern program in PHP, and pattern program in java.