1721. Two Sides of the Same Coin

http://acm.timus.ru/problem.aspx?space=1&num=1721

左边：rank   3,4,7,8,11,12.........

右边：rank   5,6,9,10,13,14.........

然后匈牙利算法

代码：

#include<iostream>
#include<stdio.h>
#include<string.h>
#include<math.h>
#include<algorithm>
#include<vector>
#include<set>
#include<map>
#include<string>
#include<queue>
#include<stack>
#include <iomanip>
using namespace std;
#define LL long long
const int INF=0x3f3f3f3f;
const int N=1006;
bool visited[N];
string name[N];
string type[N];
int r[N];
int f[N];
int head[N],I;
struct node
{
    int j,next;
}side[N*N];
void add(int i,int j)
{//cout<<i<<" "<<j<<endl;
    side[I].j=j;
    side[I].next=head[i];
    head[i]=I++;
}
bool dfs(int x)
{
    for(int t=head[x];t!=-1;t=side[t].next)
    {
        int j=side[t].j;
        if(!visited[j])
        {
            visited[j]=true;
            if(f[j]==-1||dfs(f[j]))
            {
                f[j]=x;
                return true;
            }
        }
    }
    return false;
}
inline bool L(int i)
{
    if((r[i]-3)%4==0||(r[i]-4)%4==0)
    return true;
    return false;
}
int main()
{
    //freopen("data.in","r",stdin);
    int n;
    while(cin>>n)
    {
        memset(head,-1,sizeof(head));
        I=0;
        for(int i=0;i<n;++i)
        {
            cin>>name[i]>>type[i]>>r[i];
            for(int j=0;j<i;++j)
            {
                if(abs(r[i]-r[j])==2&&(type[i]!=type[j]||type[i]=="anything"))
                {
                    if(L(i)&&!L(j))
                    add(i,j);
                    if(L(j)&&!L(i))
                    add(j,i);
                }
            }
        }
        int ans=0;
        memset(f,-1,sizeof(f));
        for(int i=0;i<n;++i)
        {
            if(L(i))
            {
                memset(visited,false,sizeof(visited));
                if(dfs(i))
                ++ans;
            }
        }
        cout<<ans<<endl;
        for(int i=0;i<n;++i)
        {
            if(f[i]!=-1)
            {
                if(type[i]=="statements"||type[f[i]]=="testdata")
                cout<<name[i]<<" "<<name[f[i]]<<endl;
                else
                cout<<name[f[i]]<<" "<<name[i]<<endl;
            }
        }

    }
    return 0;
}