C program to print the following pattern : 1 2 2 3 3 4 4 3 3 2 2 1

C program to print the following pattern :

      1
    2   2
  3       3
4           4
  3       3
    2   2
      1

Solution:

#include <stdio.h> int main(void) { int i,j,n,flip; scanf("%d",&n); for(i=1;i<=n;i++) { /* I quad */ for(j=n-i;j>=1;j--) { printf(" "); } flip=1; for(j=i;j>=1;j--) { if(flip) { printf("%d",j); flip=0; } else printf(" "); } /* quad II */ for(j=2;j<=i;j++) { if(j==i) printf("%d",j); else printf(" "); } printf("\n"); } for(i=1;i<=n-1;i++) { /* III quad */ for(j=1;j<=i;j++) { printf(" "); } flip=1; for(j=n-i;j>=1;j--) { if(flip) { printf("%d",j); flip=0; } else printf(" "); } /* quad IV *//* for(j=n-2;j>=1;j--) { if(j==i) printf("%d",j); else printf("*"); }*/ for(j=n-i;j>=1;j--) { if(j==2) printf("%d",n-i); else printf(" "); } printf("\n"); } return 0; }