50 years, 50 colors HDU

#include<bits/stdc++.h>
using namespace std;
#define MAXI 105
int mp[MAXI][MAXI];
int used[MAXI];
int vis[MAXI];
int n,m;
int color[51];
bool dfs(int  x,int color)
{
    for(int j=1;j<=n;j++)
    {
        if(mp[x][j]==color&&!used[j])
        {
            used[j]=1;
            if(!vis[j]||dfs(vis[j],color))
              {
                  vis[j]=x;
                  return true;
              }
        }
    }
    return false;
}

int find1(int x)
{    int ans=0;
 memset(vis,0,sizeof(vis));
     for(int i=1;i<=n;i++)
       {
           memset(used,0,sizeof(used));
           if(dfs(i,x))ans++;
       }
       return ans;
}

int main()
{
  int k;
   while(scanf("%d%d",&n,&k)==2&&(n||k))
   {
       int ans[MAXI];
       memset(color,0,sizeof(color));
       memset(ans,0,sizeof(ans));

        for(int i=1;i<=n;i++)
        for(int j=1;j<=n;j++)
         {
           scanf("%d",&mp[i][j]);
           color[mp[i][j]]=1;
         }

       int n=0;
       for(int i=1;i<=50;i++)
       {
           if(color[i])
           {
               if(k<find1(i))
                   ans[n++]=i;
           }
       }

       sort(ans,ans+n);

       if(n==0)printf("-1\n");
       else
        {
         for(int i=0;i<n-1;i++)
           printf("%d ",ans[i]);
           printf("%d\n",ans[n-1]);
        }

   }
  return 0;
}