CSES – Coin Combinations I

#include<bits/stdc++.h>
#define int long long
#define fastio ios_base::sync_with_stdio(0);cin.tie(0)
using namespace std;
//declare
const int mod = 1e9+7;
int n,x,dp[1000005];
vector<int> c;
//
signed main(){
    fastio;
    cin>>n>>x;
    for(int i=0;i<n;i++){
        int a; cin>>a;
        c.push_back(a);
    }
    dp[0] = 1;
    for(int i=1;i<=x;i++){
        for(int j=0;j<n;j++){
            if(i-c[j] >= 0){
                dp[i] += dp[i-c[j]];
                dp[i] %= mod;
            }
        }
    }
    cout<<dp[x] % mod<<"\n";
    return 0;
}