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;
}