[牛客] little w and Exchange

 #include <bits/stdc++.h>
using namespace std;
#define mset(var,val) memset(var,val,sizeof(var))
#define lowbit(x) (x&-x)
#define ls(i) i<<1
#define rs(i) i<<1|1
typedef long long int lli;
typedef unsigned long long ull;
const ull base=131;
const int INF=0x3f3f3f3f;
const double PI=acos(-1.0);
const long double eps=1e-20;
const int mod=1e9+7;
const int M=10010;
int main(int argc, char const *argv[])
{
 int n,m,a[M];
 scanf("%d%d",&n,&m);
 for(int i=0;i<n;i++)
  scanf("%d",&a[i]);
 sort(a,a+n);
 int now=0;
 for(int i=0;i<n;i++)
  if(a[i]<=now+1)now+=a[i];
  else break;
 if(now>=m)cout<<YES<<endl;
 else cout<<NO<<endl;
}