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
from collections import defaultdict as ddic, deque, Counter
from itertools import permutations, combinations, product
import bisect, heapq

rr = raw_input
rri = lambda: int(raw_input())
rrm = lambda: map(int, raw_input().split())

def solve(N, M, A, ops):
    A.sort()
    ops.sort(key = lambda z: z[1], reverse = True)
    i = 0
    for B, C in ops:
        for _ in xrange(B):
            A[i] = max(A[i], C)
            i += 1
            if i == N: return sum(A)
    return sum(A)
        

N, M = rrm()
A = rrm()
ops = [rrm() for _ in xrange(M)]
print solve(N, M, A, ops)
