20pts，只求50pts

lihyit @ 2025-01-10 16:14:55

#include<bits/stdc++.h>
using namespace std;
int a[50],ans;
int n,m;
void dfs(int num,int sum)
{
    if(num>n)
    {
        if(sum<=m)ans++;
        return ;
    }
    dfs(num+1,sum+a[num]);
    dfs(num+1,sum);
}
int main()
{
    cin>>n>>m;
    for(int i=1;i<=n;i++) cin>>a[i];
    dfs(1,0);
    cout<<ans<<endl;
    return 0;
}

by lihyit @ 2025-01-10 16:18:44

这个算法，50不行，顶多40 40解：

#include<bits/stdc++.h>
using namespace std;
long long a[50],ans;
long long n,m;
void dfs(long long num,long long sum)
{
    if(num>n)
    {
        if(sum<=m)ans++;
        return ;
    }
    dfs(num+1,sum+a[num]);
    dfs(num+1,sum);
}
int main()
{
    cin>>n>>m;
    for(long long i=1;i<=n;i++) cin>>a[i];
    dfs(1,0);
    cout<<ans<<endl;
    return 0;
}