Watashi's BG(搜索)

http://acm.zju.edu.cn/onlinejudge/showProblem.do?problemCode=3631

#include <iostream>
#include <cmath>
#include <cstdio>
#include <algorithm>
using namespace std;
int arr[50];
int n,mx,m;
void dfs(int cur,int total)
{
    if(mx==m) return ;
    if(total>mx&&total<=m) mx=total;
    for(int i=cur+1;i<n;i++) if(total+arr[i]<=m)
    {
        dfs(i,total+arr[i]);
    }
}
int main()
{
    int sum;
    while(cin>>n>>m)
    {
        mx=0;sum=0;
        for(int i=0;i<n;i++) {scanf("%d",arr+i);sum+=arr[i];}
        if(sum<=m) {cout<<sum<<endl;continue;}
        for(int i=0;i<n;i++) dfs(i,arr[i]);
        cout<<mx<<endl;
    }
    return 0;
}