CF257A.Sockets

普及/提高-

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题目描述

Vasya has got many devices that work on electricity. He's got nn supply-line filters to plug the devices, the ii -th supply-line filter has aia_{i} sockets.

Overall Vasya has got mm devices and kk electrical sockets in his flat, he can plug the devices or supply-line filters directly. Of course, he can plug the supply-line filter to any other supply-line filter. The device (or the supply-line filter) is considered plugged to electricity if it is either plugged to one of kk electrical sockets, or if it is plugged to some supply-line filter that is in turn plugged to electricity.

What minimum number of supply-line filters from the given set will Vasya need to plug all the devices he has to electricity? Note that all devices and supply-line filters take one socket for plugging and that he can use one socket to plug either one device or one supply-line filter.

输入格式

The first line contains three integers nn , mm , kk ( 1<=n,m,k<=501<=n,m,k<=50 ) — the number of supply-line filters, the number of devices and the number of sockets that he can plug to directly, correspondingly. The second line contains nn space-separated integers a1,a2,...,ana_{1},a_{2},...,a_{n} ( 1<=ai<=501<=a_{i}<=50 ) — number aia_{i} stands for the number of sockets on the ii -th supply-line filter.

输出格式

Print a single number — the minimum number of supply-line filters that is needed to plug all the devices to electricity. If it is impossible to plug all the devices even using all the supply-line filters, print -1.

输入输出样例

  • 输入#1

    3 5 3
    3 1 2
    

    输出#1

    1
    
  • 输入#2

    4 7 2
    3 3 2 4
    

    输出#2

    2
    
  • 输入#3

    5 5 1
    1 3 1 2 1
    

    输出#3

    -1
    

说明/提示

In the first test case he can plug the first supply-line filter directly to electricity. After he plug it, he get 5 (3 on the supply-line filter and 2 remaining sockets for direct plugging) available sockets to plug. Thus, one filter is enough to plug 5 devices.

One of the optimal ways in the second test sample is to plug the second supply-line filter directly and plug the fourth supply-line filter to one of the sockets in the second supply-line filter. Thus, he gets exactly 7 sockets, available to plug: one to plug to the electricity directly, 2 on the second supply-line filter, 4 on the fourth supply-line filter. There's no way he can plug 7 devices if he use one supply-line filter.

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