ITSA 2017 Apr 5.cpp

ITSA 2017 Apr 5.cpp

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

int main()
{	
	int ncase;
	scanf("%d", &ncase);

	while(ncase--) {
		int n;
		scanf("%d", &n);
		ll inp[n];
		for(int i = 0; i < n; i++) {
			scanf("%lld", &inp[i]);
		}
		
		int cnt[n];
		ll base = 1LL;
		for(int i = n - 1; i >= 0; i--) {
			cnt[i] = base;
			base <<= 1;
		}

		ll ans = 0;
		for(int i = 0; i < n; i++) {
			ans += cnt[i] * inp[i];
		}

		printf("%lld\n", ans);
	}
	return 0;
}