1632: 5017. 垦田计划
Memory Limit:128 MB
Time Limit:1.000 S
Judge Style:Text Compare
Creator:
Submit:17
Solved:11
Description

二分、差分、贪心都可以求解!
Input

Output

Sample Input Copy
4 9 2
6 1
5 1
6 2
7 1
Sample Output Copy
5
HINT

