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
# coding:utf-8

import math
import re

def main(params):
    n,m = params[0]
    a = params[1]
    tmpA = []
    for i in a:
        i = int(i)
        tmpA.append(i)
    a = tmpA
    a.sort()
    a.reverse()
    r = {}
    for g in params[2:]:
        b = int(g.split()[0])
        c = int(g.split()[1])
        if c not in r:
            r[c] = b
        else:
            r[c] += b
#        t = [c] * b
#        r.extend(t)
#    r.sort()
#    r.reverse()
    rV = r.keys()
    rV.sort()
    rV.reverse()
    cnt = 0
    total = 0L
    while True:
        if len(a) == 0:
            total += rV[0]
            r[rV[0]] -= 1
            if r[rV[0]] == 0:
                rV.pop(0)
        elif len(rV) == 0:
            total += a[0]
            a.pop(0)
        elif a[0] < rV[0]:
            total += rV[0]
            r[rV[0]] -= 1
            if r[rV[0]] == 0:
                rV.pop(0)
        else:
            total += a[0]
            a.pop(0)
        cnt += 1
        if cnt == n:
            break
    print total
#    a = params[1].split()
#    b = list(params[2])

if __name__ == "__main__":
    n,m = raw_input().split()
    n = int(n)
    m = int(m)
    a = raw_input().split()
    cnt = m # TODO: edit here
    params = [[n,m],a]
    for i in range(cnt):
        param = raw_input()
        params.append(param)
    main(params)

