Problem Description

At Kyoto University, there are $ N $ lectures offered this semester, and you need to earn at least $ K $ credits to advance to the next level.

The number of credits assigned to the $ i $th lecture is $ a_i $. You want to advance with the minimum number of courses taken. Determine how many lectures you need to take.

Input Format

The input is given from the standard input in the following format:

$ N $ $ K $ $ a_1 $ $ a_2 $ $ ... $ $ a_N $

Output Format

Find the minimum number of courses needed. If you cannot earn enough credits even after taking all the lectures, output -1 instead.

Sample Input and Output

Sample Input #1

5 15
3 8 2 5 6

Sample Output #1

3

Sample Input #2

5 25
3 8 2 5 6

Sample Output #2

-1

Sample Input #3

4 20
1 1 20 19

Sample Output #3

1

Notes/Hints

Constraints

• $1 \leq N \leq 50$
• $1 \leq K \leq 1,000$
• $1 \leq a_i \leq 20$
• $ N $, $ K $, $ a_i $ are integers.

Sample Explanation 1

For example, you can take the $ 1 $, $ 2 $, and $ 4 $th lectures.

Sample Explanation 2

You cannot earn enough credits even after taking all the lectures.

见题面 Input 部分

见题面 Output 部分