Problem7541--[CSES Problem Set] Coin Combinations I

7541: [CSES Problem Set] Coin Combinations I

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Time Limit : 1.000 sec  Memory Limit : 256 MiB

Description

Consider a money system consisting of $n$ coins. Each coin has a positive integer value. Your task is to calculate the number of distinct ways you can produce a money sum $x$ using the available coins.
For example, if the coins are $\{2,3,5\}$ and the desired sum is $9$, there are $8$ ways:
  • 2+2+5
  • 2+5+2
  • 5+2+2
  • 3+3+3
  • 2+2+2+3
  • 2+2+3+2
  • 2+3+2+2
  • 3+2+2+2

Input

The first input line has two integers $n$ and $x$: the number of coins and the desired sum of money.
The second line has $n$ distinct integers $c_1,c_2,\dots,c_n$: the value of each coin.

Output

Print one integer: the number of ways modulo $10^9+7$.

Constraints

$1≤n≤100$
$1 \le x \le 10^6$
$1 \le c_i \le 10^6$

Sample 1 Input

3 9
2 3 5

Sample 1 Output

8

HINT

相同题目:CSES 1635

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