#include <cstdio>

long long s[10000005];

int main() {
    int n, m;
    scanf("%d%d", &n, &m);

    for (int i = 1; i <= n; i++) {
        int x;
        scanf("%d", &x);
        s[i] = s[i-1] + x;
    }

    while (m--) {
        int l, r;
        scanf("%d%d", &l, &r);
        printf("%lld\n", s[r] - s[l-1]);
    }

    return 0;
}