NYOJ--927--dfs--The partial sum problem

/*Name: NYOJ--927--The partial sum problemAuthor: shen_渊 Date: 15/04/17 19:41Description: DFS,和 NYOJ--1058--dfs--部分和问题 基本一致，递归的i+1注意了，其他没什么 
*/#include<cstring>
#include<iostream>
using namespace std;
void dfs(int);
int arr[22],vis[22];
int n,k,sum,flag;
int main()
{
//    freopen("in.txt","r",stdin);while(cin>>n){memset(vis,0,sizeof(vis));memset(arr,0,sizeof(arr));flag = 0;for(int i=0; i<n; ++i)cin>>arr[i];cin>>k;dfs(0);if(flag)cout<<"Of course,I can!\n";else cout<<"Sorry,I can't!\n";}return 0;
}
void dfs(int ct)
{if(sum == k){flag = 1;return ;}for(int i=ct; i<n; ++i){if(sum+arr[i] <= k){vis[i] = 1;sum += arr[i];dfs(i+1);sum -= arr[i];vis[i] = 0;if(flag)return;}}
}