The correct, optimal and working solution for programming question mandragora on hackerrank

/* * Author: Arpit Bhayani * https://arpitbhayani.me */ #include <cmath> #include <cstdio> #include <cstdlib> #include <climits> #include <deque> #include <iostream> #include <list> #include <limits> #include <map> #include <queue> #include <set> #include <stack> #include <vector> #define ll long long #define MIN(a, b) a < b ? a : b #define MAX(a, b) a > b ? a : b using namespace std; int readline(char *str) { int i = 0; char ch; while((ch = getchar()) != '\n') { str[i++] = ch; } str[i] = '\0'; return i; } ll int arr[100010]; int compar(const void * a, const void * b) { return (*(int *)a) > (*(int *)b); } int main(int argc, char *argv[]) { int t; scanf("%d", &t); while(t--) { int n; ll int sum = 0; scanf("%d", &n); for(int i = 0; i < n; i++) { scanf("%lld", &arr[i]); sum += arr[i]; } qsort(arr, n , sizeof(ll int), compar); ll int op, tp, temp_sum = sum; op = (0 + 1) * temp_sum; for(int x = 1; x < n; x++) { temp_sum -= arr[x-1]; tp = (x + 1) * temp_sum; if(tp < op) { break; } op = MAX(tp, op); } printf("%lld\n", op); } return 0; }