You have N cards. On the i-th card, an integer A_i is written.

For each j = 1, 2, ..., M in this order, you will perform the following operation once:

Operation: Choose at most B_j cards (possibly zero). Replace the integer written on each chosen card with C_j.

Find the maximum possible sum of the integers written on the N cards after the M operations.

Constraints

* All values in input are integers.
* 1 \leq N \leq 10^5
* 1 \leq M \leq 10^5
* 1 \leq A_i, C_i \leq 10^9
* 1 \leq B_i \leq N

Input

Input is given from Standard Input in the following format:


N M
A_1 A_2 ... A_N
B_1 C_1
B_2 C_2
\vdots
B_M C_M


Output

Print the maximum possible sum of the integers written on the N cards after the M operations.

Examples

Input

3 2
5 1 4
2 3
1 5


Output

14


Input

10 3
1 8 5 7 100 4 52 33 13 5
3 10
4 30
1 4


Output

338


Input

3 2
100 100 100
3 99
3 99


Output

300


Input

11 3
1 1 1 1 1 1 1 1 1 1 1
3 1000000000
4 1000000000
3 1000000000


Output

10000000001
#include <iostream>
#include <algorithm>
#include <vector>
#include <string>
#define int long long
using namespace std;
int n, m, a[123456];
pair<int, int>p[123456];
signed main() {
	cin >> n >> m;
	for (int i = 0; i < n; i++)cin >> a[i]; sort(a, a + n);
	for (int i = 0; i < m; i++)cin >> p[i].second >> p[i].first;
	sort(p, p + m);
	int am = 0;
	for (int i = m - 1; i >= 0; i--) {
		for (int j = 0; j < p[i].second&&am < n; j++) {
			a[am] = max(a[am], p[i].first);
			am++;
		}
	}
	am = 0; for (int i = 0; i < n; i++)am += a[i];
	cout << am << endl;
	cin >> n;
}