#54200: C++ 使用前綴和
hch980506@gmail.com
(申有娜我老婆)
把cin,cout 改scanf,printf會快一些
#include <cstdio>
#include <vector>
using namespace std;
int main() {
int n;
scanf("%d", &n);
vector<int> num(n);
vector<long long> pre(n);
for (int i = 0; i < n; i++) {
scanf("%d", &num[i]);
if (i == 0) {
pre[0] = num[0];
continue;
}
pre[i] = pre[i - 1] + num[i];
}
int q;
scanf("%d", &q);
while (q--) {
int l, r;
scanf("%d %d", &l, &r);
long long total = 0;
if (l == 1)
total = pre[r - 1];
else
total = pre[r - 1] - pre[l - 2];
printf("%lld\n", total);
}
}