C program for pyramid/triangle number pattern 22

This program is to print pyramid/triangle number pattern 22 in C.

1
121
12321
1234321
123454321
12345654321
1234567654321

Dry Run of the Program

Let us take no of lines ‘n’ = 3

Outer For Loop 1st iteration

for(i=1;i<=n;i++ ) i.e. for(i=1;1<=3;i++ )

1st Inner For Loop 1st iteration

for(j=1;j<=n-i;j++) i.e. for(j=1;1<=2;j++)

print(” “) // space

1st Inner For Loop 2nd iteration

for(j=2;j<=n-i;j++) i.e. for(j=2;2<=2;j++)

print(” “) // space

2nd Inner For Loop 1st iteration

for(j=1;j<=i;j++) i.e. for(j=1;1<=1;j++)

printf(“%d”,j); i.e. print 1 //leaving 2 spaces from left

3rd Inner For Loop is not executed as j=i-1(i.e. j=0) 0>=1

printf(“\n”) i.e. Leave a line

Outer For Loop 2nd iteration

for(i=2;i<=n;i++ ) i.e. for(i=2;2<=3;i++ )

1st Inner For Loop 1st iteration

for(j=1;j<=n-i;j++) i.e. for(j=1;1<=1;j++)

print(” “) // space

2nd Inner For Loop 1st iteration

for(j=1;j<=i;j++) i.e. for(j=1;1<=2;j++)

printf(“%d”,j); i.e. print 1 //leaving 1 space from left

2nd Inner For Loop 2nd iteration

for(j=2;j<=i;j++) i.e. for(j=2;2<=2;j++)

printf(“%d”,j); i.e. print 2 //

Output till now

__1

_12

3rd Inner For Loop 1st iteration

for(j=i-1;j>=1;j–) i.e. for(j=1;1>=1;j–)

printf(“%d”,j) i.e. print 1

Output till now

__1

_121

printf(“\n”) i.e. Leave a line

Outer For Loop 3rd iteration

for(i=3;i<=n;i++ ) i.e. for(i=3;3<=3;i++ )

1st Inner For Loop is not executed as j(1) is not j(1)<=0

2nd Inner For Loop 1st iteration

for(j=1;j<=i;j++) i.e. for(j=1;1<=3;j++)

printf(“%d”,j); i.e. print 1

2nd Inner For Loop 2nd iteration

for(j=2;j<=i;j++) i.e. for(j=2;2<=3;j++)

printf(“%d”,j); i.e. print 2 //

2nd Inner For Loop 3rd iteration

for(j=3;j<=i;j++) i.e. for(j=3;3<=3;j++)

printf(“%d”,j); i.e. print 3 //

Output till now

__1

_121_

123

3rd Inner For Loop 1st iteration

for(j=i-1;j>=1;j–) i.e. for(j=2;2>=1;j–)

printf(“%d”,j) i.e. print 2

3rd Inner For Loop 2nd iteration

for(j=i-1;j>=1;j–) i.e. for(j=1;1>=1;j–)

printf(“%d”,j) i.e. print 1

Final Output

__1__

_121_

12321

Program

#include<stdio.h>

void main()
{
        int i,n,j;
        
        printf("Enter the no of lines\n");
        scanf("%d",&n);
        
        for(i=1;i<=n;i++)
        {
            for(j=1;j<=n-i;j++)
            {
                printf(" ");
            }
            for(j=1;j<=i;j++)
            {
                printf("%d",j);
            }
            for(j=i-1;j>=1;j--)
            {
                printf("%d",j);
            }
            printf("\n");
        }
}

CODEDOST

C program for pyramid/triangle number pattern 22