题目描述
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
输入格式
见题面
输出格式
见题面