#include <iostream>
#include <cstdio>
using namespace std;
#define LL long long 
int main() {
	int n, m;
	scanf("%d %d", &n, &m);
	int grass[n];
	LL grass_height[n];
	for(int i = 0; i < n; ++i) {
		scanf("%d", &grass[i]);
		grass_height[i] = 0;
	}
	
	int current_day = 0;
	int day, height;
	for(int t = 0; t < m; ++t) {
		scanf("%d%d", &day, &height);
		LL sum = 0;
		for(int i = 0; i < n; ++i) {
			grass_height[i] += (LL)(day-current_day)*(LL)grass[i];
			if(grass_height[i] > height) {
				sum += grass_height[i] - height;
				grass_height[i] = height;
			}
		}
		
		printf("%lld\n", sum);
		current_day = day;
	}
	return 0;
}