Envío 581

Código

#include <iostream>
#include <vector>
#include <cassert>
using namespace std;

int main() {
  int n;
  cin >> n;
  vector<int> a(n);
  for (int i = 0; i < n; ++i) {
    cin >> a[i];
  }
  assert(n > 0);
  vector<int> sum(n);
  for (int i = 0; i < n; ++i) {
    sum[i] = a[i];
    if (i - 1 >= 0) sum[i] += sum[i - 1];
  }


  int c;
  cin >> c;
  while (c--) {
    int p, q;
    cin >> p >> q;
    int answer = sum[q];
    if (p - 1 >= 0) {
      answer -= sum[p - 1];
    }
    cout << answer << endl;
  }

  return 0;
}