include <stdio.h>

int main() {

int a[1000010];
int sum[1000010];
int n, m;
scanf("%d %d", &n, &m);
for (int i = 1; i <= n; i++) {
	scanf("%d", &a[i]);
}
sum[0] = 0;
for (int i = 1; i <= n; i++) {
	sum[i] = sum[i - 1] + a[i];
}
for (int i = 0; i < m; i++) {
	int l, r;
	scanf("%d %d", &l, &r);
	printf("%d\n", sum[r] - sum[l - 1]);
}
return 0;

}