C Program to Print Triangle of Numbers in Reverse Pattern

Write a C program to print triangle of numbers in reverse pattern using for loop.

#include <stdio.h>

int main()
{
	int rows;

	printf("Enter Triangle of Numbers in Reverse Rows = ");
	scanf("%d", &rows);

	printf("Triangle of Numbers in Reverse Order Pattern\n");

	for (int i = rows; i >= 1; i--)
	{
		for (int j = 1; j < i; j++)
		{
			printf(" ");
		}
		for (int k = i; k <= rows; k++)
		{
			printf("%d ", k);
		}
		printf("\n");
	}
}

This C program prints the triangle pattern of numbers in descending order or reverse order using a while loop.

#include <stdio.h>

int main()
{
	int i, j, k, rows;
	
	printf("Enter Triangle of Numbers in Reverse Rows = ");
	scanf("%d", &rows);

	printf("Triangle of Numbers in Reverse Order Pattern\n");
	i = rows;

	while (i >= 1)
	{
		j = 1;
		while (j < i)
		{
			printf(" ");
			j++;
		}

		k = i;
		while (k <= rows)
		{
			printf("%d ", k);
			k++;
		}

		printf("\n");
		i--;
	}
}

Enter Triangle of Numbers in Reverse Rows = 9
Triangle of Numbers in Reverse Order Pattern
        9 
       8 9 
      7 8 9 
     6 7 8 9 
    5 6 7 8 9 
   4 5 6 7 8 9 
  3 4 5 6 7 8 9 
 2 3 4 5 6 7 8 9 
1 2 3 4 5 6 7 8 9 

This C example uses the do while loop to print the triangle of numbers in reverse order pattern.

#include <stdio.h>

int main()
{
	int i, j, k, rows;

	printf("Enter Triangle of Numbers in Reverse Rows = ");
	scanf("%d", &rows);

	printf("Triangle of Numbers in Reverse Order Pattern\n");
	i = rows;

	do
	{
		j = 1;
		do
		{
			printf(" ");

		} while (j++ < i);

		k = i;
		do
		{
			printf("%d ", k);

		} while (++k <= rows);

		printf("\n");

	} while (--i >= 1);
}

Enter Triangle of Numbers in Reverse Rows = 5
Triangle of Numbers in Reverse Order Pattern
     5 
    4 5 
   3 4 5 
  2 3 4 5 
 1 2 3 4 5