include

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;

}