Shared code

#include<iostream>
#include<vector>
using namespace std;
#define M 1000000007

vector<int>arr;
vector<vector<int>>dp;

int solve(int i,int target){
    if(i>=(int)arr.size()) return 0;
    if(target<0) return 0;
    if(target==0) return 1;
    if(dp[i][target]!=-1) return dp[i][target];
    return dp[i][target]=(solve(i,target-arr[i])%M+solve(i+1,target)%M)%M;
}

int main(){
    int n,target;
    cin>>n>>target;
    arr.resize(n);
    dp.resize(n+1,vector<int>(target+1,-1));
    for(int i=0;i<n;++i){
        cin>>arr[i];
    }
    cout<<solve(0,target);
}