Ningbo [1218] You are my brother(注意数组的大小)

1、http://cdn.ac.nbutoj.com/Problem/view.xhtml?id=1218

2、题目：

• [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

#include<stdio.h>
#include<math.h>
#include<iostream>
#include<string.h>
#include<algorithm>
using namespace std;
int f[3005];
int main()
{int n,a,b;while(scanf("%d",&n)!=EOF){memset(f,-1,sizeof(f));for(int i=1;i<=n;i++){scanf("%d%d",&a,&b);f[a]=b;}int p=1;int sum=0;while(f[p]!=-1){sum++;p=f[p];}p=2;int count=0;while(f[p]!=-1){count++;p=f[p];}if(count>sum)printf("You are my younger\n");else if(count<sum)printf("You are my elder\n");elseprintf("You are my brother\n");}return 0;
}