【递归】油桶问题

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <algorithm>
#include <climits>
#include <cstring>
#include <string>
#include <set>
#include <map>
#include <queue>
#include <stack>
#include <vector>
#include <list>
#define rep(i,m,n) for(i=m;i<=n;i++)
#define rsp(it,s) for(set<int>::iterator it=s.begin();it!=s.end();it++)
#define mod 1000000007
#define inf 0x3f3f3f3f
#define vi vector<int>
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define ll long long
#define pi acos(-1.0)
const int maxn=1e4+10;
const int dis[][2]={0,1,-1,0,0,-1,1,0};
using namespace std;
ll gcd(ll p,ll q){return q==0?p:gcd(q,p%q);}
ll qpow(ll p,ll q){ll f=1;while(q){if(q&1)f=f*p%mod;p=p*p%mod;q>>=1;}return f;}
int a[maxn]={1};
int main()
{
    int i,j,m,n,k,t;
    scanf("%d%d",&n,&m);
    rep(i,0,n-1)
    {
        scanf("%d",&k);
        if(k<=m)
        {
            for(j=m;j>=k;j--)a[j]|=a[j-k];
        }
    }
    printf("%s\n",a[m]?"yes":"no");
    //system("pause");
    return 0;
}