#include <iostream>
#include <vector>

int main(int argc, char* argv[]) {
	unsigned n, m;
	std::cin >> n >> m;
	std::vector<unsigned> a(n);
	for (unsigned i = 0; i < n; ++i) {
		std::cin >> a[i];
	}
	unsigned long long day = 0;
	std::vector<unsigned long long> field(n, 0);
	for (unsigned i = 0; i < m; ++i) {
		unsigned long long d, b;
		std::cin >> d >> b;
		unsigned long long simDays = d - day;
		unsigned long long cut = 0;
		for (unsigned j = 0; j < n; ++j) {
			field[j] += simDays * a[j];
			if (field[j] > b) {
				cut += field[j] - b;
				field[j] = b;
			}
		}
		std::cout << cut << std::endl;
		day = d;
	}
	return 0;
}