4757: P1208 [USACO1.3] 混合牛奶 Mixing Milk(普及-)
Memory Limit:128 MB
Time Limit:1.000 S
Judge Style:Text Compare
Creator:
Submit:0
Solved:0
Description

Input

Output

Sample Input Copy
100 5
5 20
9 40
3 10
8 80
6 30
Sample Output Copy
630
HINT
