구현 26분
#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <vector>
using namespace std;
long Array[100001];
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
//freopen("input.txt", "rt", stdin);
int N{}, M{};
cin >> N >> M;
for (int i = 1; i <= N; ++i)
{
cin >> Array[i];
Array[i] += Array[i - 1];
}
int i{}, j{};
for (int k = 0; k < M; ++k)
{
cin >> i >> j;
cout << Array[j] - Array[i - 1] << '\n';
}
return 0;
}