fzoj1314 You are my brother

题目描述

Little A gets to know a new friend, Little B, recently. One day, they realize that they are family 500 years ago. Now, Little A wants to know whether Little B is his elder, younger or brother.

 

输入

There are multiple test cases.

For each test case, the first line has a single integer, n (n<=1000). The next n lines have two integers a and b (1<=a,b<=2000) each, indicating b is the father of a. One person has exactly one father, of course. Little A is numbered 1 and Little B is numbered 2.

Proceed to the end of file.

输出

For each test case, if Little B is Little A’s younger, print “You are my younger”. Otherwise, if Little B is Little A’s elder, print “You are my elder”. Otherwise, print “You are my brother”. The output for each test case occupied exactly one line.

 

样例输入

5
1 3
2 4
3 5
4 6
5 6
6
1 3
2 4
3 5
4 6
5 7
6 7

样例输出

You are my elder
You are my brother

#include<iostream>
#include<cstring>
using namespace std;
int main()
{
    int n;
    while(cin>>n)
    {
        int a,b,la=1,lb=2,da=0,db=0;
        for(int i=1;i<=n;i++)
        {
            cin>>a>>b;
            if(la==a){la=b;da++;}
            if(lb==a){lb=b;db++;}
        }
        if(db<da)cout<<"You are my elder"<<endl;
        else if(db==da) cout<<"You are my brother"<<endl;
        else if(db>da) cout<<"You are my younger"<<endl;
    }
    return 0;
}