静态区间前缀和
#include<bits/stdc++.h>
using namespace std;
#define int long long
signed main()
{
std::ios::sync_with_stdio(false);
std::cin.tie(0);
std::cout.tie(0);
int n, q;
cin >> n >> q;
vector<int> z;
for (int i = 0; i < n; i++)
{
int temp;
cin >> temp;
z.push_back(temp);
}
vector<int> sum(n + 1, 0);
for (int i = 1; i <= n; i++)
{
sum[i] = sum[i - 1] + z[i - 1];
}
while (q > 0)
{
int l, r;
cin >> l >> r;
int suml = sum[r] - sum[l - 1];
cout << suml << endl;
q--;
}
return 0;
}