C program to Print Sandglass Number Pattern

Write a C program to print sandglass number pattern using for loop. 

#include <stdio.h>

int main()
{
    int i, j, k, rows;
    
    printf("Enter Sandglass Number Pattern Rows = ");
    scanf("%d",&rows);

    printf("The Sandglass Number Pattern\n"); 

	for (i = 1 ; i <= rows; i++ ) 
	{
		for (j = 1; j < i; j++ ) 	
		{
			printf(" ");
		}
		for (k = i; k <= rows; k++ ) 	
		{
			printf("%d ", k);
		}
		printf("\n");
	}
    
    for (i = rows - 1; i >= 1; i-- ) 
	{
		for (j = 1; j < i; j++ ) 	
		{
			printf(" ");
		}
		for (k = i; k <= rows; k++ ) 	
		{
			printf("%d ", k);
		}
		printf("\n");
	}
		
    return 0;
}

This C example prints the numbers in a sandglass pattern using a while loop.

#include <stdio.h>

int main()
{
    int i = 1, j, k, rows;
    
    printf("Enter Sandglass Number Pattern Rows = ");
    scanf("%d",&rows);

    printf("\nThe Sandglass Number Pattern\n"); 

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

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

        k = i;
        while( k <= rows )
        {
			printf("%d ", k);
		    k++;
        }
		printf("\n");
		i--;
	}
		
    return 0;
}

Enter Sandglass Number Pattern Rows = 7

The Sandglass Number Pattern
1 2 3 4 5 6 7 
 2 3 4 5 6 7 
  3 4 5 6 7 
   4 5 6 7 
    5 6 7 
     6 7 
      7 
     6 7 
    5 6 7 
   4 5 6 7 
  3 4 5 6 7 
 2 3 4 5 6 7 
1 2 3 4 5 6 7

C program to display the sandglass number pattern using a do while loop.

#include <stdio.h>

int main()
{
    int i = 1, j, k, rows;
    
    printf("Enter Sandglass Number Pattern Rows = ");
    scanf("%d",&rows);

    printf("\nThe Sandglass Number Pattern\n"); 

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

        } while( j++ < i);

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

		} while( ++k <= rows );
		printf("\n");

	} while( ++i <= rows);
    
    i = rows - 1;
    do
    {
        j = 1;
    	do
		{
			printf(" ");
			
        } while( j++ < i);

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

        } while( ++k <= rows );
		printf("\n");

	} while( --i >= 1);
		
    return 0;
}

Enter Sandglass Number Pattern Rows = 9

The Sandglass Number Pattern
 1 2 3 4 5 6 7 8 9 
  2 3 4 5 6 7 8 9 
   3 4 5 6 7 8 9 
    4 5 6 7 8 9 
     5 6 7 8 9 
      6 7 8 9 
       7 8 9 
        8 9 
         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