USACO holstein AC code

/*
ID:kevin_s1
PROG:holstein
LANG:C++
*/

#include <iostream>
#include <cstdio>
#include <string>
#include <cstring>
#include <vector>
#include <map>
#include <set>
#include <algorithm>
#include <cstdlib>
#include <list>
#include <cmath>

using namespace std;

#define MAXV 26
#define MAXG 16
#define INF 327699

//gobal variable====
int V;
int requirement[MAXV];
int G;
int feed[MAXG][MAXV];
int result;

int ans[MAXG];
int vit[MAXV];
int res[MAXG];
//==================

//function==========
bool check(){
bool flag = true;
for(int i = 1; i <= V; i++){
if(vit[i] < requirement[i])
flag = false;
}
return flag;
}

void DFS(int deep, int count){
if(deep == G + 1){
if(check() == false)
return;
if(count < result){
result = count;
for(int i = 1; i <= result; i++){
res[i] = ans[i];
}
}
return;
}
for(int i = 1; i <= V; i++){
vit[i] += feed[deep][i];
}
ans[count + 1] = deep;
DFS(deep + 1, count + 1);
for(int i = 1; i <= V; i++){
vit[i] -= feed[deep][i];
}
DFS(deep + 1, count);
return;
}

//==================

int main(){
freopen("holstein.in","r",stdin);
freopen("holstein.out","w",stdout);
cin>>V;
for(int i = 1; i <= V; i++){
cin>>requirement[i];
}
cin>>G;
for(int i = 1; i <= G; i++){
for(int j = 1; j <= V; j++){
cin>>feed[i][j];
}
}
memset(res, 0, sizeof(res));
memset(ans, 0, sizeof(ans));
memset(vit, 0, sizeof(vit));
result = INF;
DFS(1, 0);
cout<<result;
for(int i = 1; i <= result; i++){
cout<<" "<<res[i];
}
cout<<endl;
return 0;
}