题解

#include <iostream>
#include <cstdio>
#include <algorithm>
using namespace std;
int a[100005], dp[100005];
int mod = 1e9 + 7;
int main(){
	dp[0] = 1;
	int n, m;
	cin >> n >> m;
	for(int i = 1; i <= n; i++){
		cin >> a[i];
	}sort(a + 1, a + n + 1);
	for(int i = 1; i <= m; i++){
		for(int j = 1; j <= n; j++){
			if(i >= a[j]) dp[i] = (dp[i] + dp[i - a[j]]) % mod;
			else break;
		}
	}cout << dp[m];

	return 0;
}