[1218] You are my brother

柔情只为你懂 2022-02-26 04:06 130阅读 0赞

### \[1218\] You are my brother ###

*  时间限制: 1000 ms　内存限制: 131072 K
 *  问题描述
 *  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
 *  提示
 *      无
 *  来源
 *      辽宁省赛2010
    
    ## 题目大意：输入N对数a，b，表示b是a的父亲，最后求的是1和2的关系，也就是看1和2与根的关系（注意，若a和b不在同一棵树上，则他们的关系为brother） ##
 *  ## 思路：题目中说不存在两个父亲，所以我们可以定义一个数组，把一个数存到这个数上，形如a\[1\]=3,a\[3\]=5……，这样每个数就都会连到一起，最后循环找一下根深度就好了，比赛的时候数组开大了，一直超时………… ##

## 代码：     ##

#include<map>
    #include<set>
    #include<stack>
    #include<queue>
    #include<cmath>
    #include<string>
    #include<cstdio>
    #include<cstring>
    #include<cstdlib>
    #include<iostream>
    #include<algorithm>
    using namespace std;
    #define ll unsigned long long
    #define inf 0x3f3f3f3
    #define esp 1e-8
    #define bug {printf("mmp\n");}
    #define mm(a,b) memset(a,b,sizeof(a))
    #define T() int test,q=1;scanf("%d",&test); while(test--)
    const int maxn=2e7+100;
    const double pi=acos(-1.0);
    const int N=2e5+10;
    const int mod=1e9+7;
    int a[N];
    int main()
    {
    
        int n;
        while(scanf("%d",&n)!=EOF)
        {
            memset(a,0,sizeof(a));
            for(int i=0; i<n; i++)
            {
    
                int aa,bb;
                scanf("%d%d",&aa,&bb);
                a[aa]=bb;
            }
            int ans1=0,ans2=0;
            int f1=1,f2=2;
            while(a[f1])
            {
                ans1++;
                f1=a[f1];
            }
            while(a[f2])
            {
                ans2++;
                f2=a[f2];
            }
            if(ans1==ans2)
                printf("You are my brother\n");
            else if(ans1>ans2)
                printf("You are my elder\n");
            else
                printf("You are my younger\n");
        }
        return 0;
    }