1104. Sum of Number Segments (20)

#include <iostream>using namespace std;double num[100010];int main()
{int n;scanf("%d", &n);int i;for(i = 1; i <= n; i++){scanf("%lf", &num[i]);}double res = 0;for(i = 1; i <= n; i++){res += num[i] * i * (n + 1 - i);}printf("%.2lf\n", res);system("pause");return 0;
}