Solution to https://jutge.org/problems/P74421_en/statement

Christmas gift.cc

#include <iostream>
#include <vector>

using namespace std;

const int _1e5 = 100000;

int abs(int n) { return (n < 0 ? -n : n); }

int main()
{
	int n, q, a, b, res;
	int bolets[_1e5 + 1];
	int cas = 0;

	while (cin >> n) {
		cas++;
		for (int i = 0; i < n; i++) {
			cin >> bolets[i];
			if (i > 0) bolets[i] += bolets[i - 1];
		}
		cin >> q;
		cout << '#' << cas << endl;
		for (int i = 0; i < q; i++) {
			cin >> a >> b;
			res = bolets[max(a, b) - 1];
			if (min(a, b) - 2 >= 0) res -= bolets[min(a, b) - 2];
			cout << res << endl;
		}	
	}
}