#include<stdio.h> int main() {int n,i,a[1000],c[1000],j; scanf("%d",&n); for(i=0;i<2n;i++) { scanf("%d",&a[i]); } for(j=0,i=0;i<2n,j<n;i=2*j+2,j++) { c[j]=(a[i]*a[i+1]); } for(i=0;i<n;i++) printf("%d\n",c[i]); return 0; }
I guess you didn’t try any numbers with 10000 digits? Or even 20 digits? If you did, you’d see the problem.
Edit: I also expect you didn’t try the maximum number of test cases, because that would show you another problem.