Roy and Matrix Sum : HackerEarth Problem Solution

Roy and Matrix Sum : HackerEarth Problem Solution

#include <stdio.h> unsigned long long int rec(unsigned long long int N) { if(N==0) return 0; return (N*(N-1)+rec(N-1)); } int main() { unsigned long long int t,i,j,N,sum; scanf("%llu",&t); while(t--) { sum=0; scanf("%llu",&N); sum=rec(N); printf("%llu\n",sum); } return 0; }