hdu 1563

 

Find your present!

Time Limit: 1000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 4052    Accepted Submission(s): 2674

Problem Description

In the new year party, everybody will get a "special present".Now it's your turn to get your special present, a lot of presents now putting on the desk, and only one of them will be yours.Each present has a card number on it, and your present's card number will be the one that different from all the others.For example, there are 5 present, and their card numbers are 1, 2, 3, 2, 1.so your present will be the one with the card number of 3, because 3 is the number that different from all the others.

 

Input

The input file will consist of several cases. 
Each case will be presented by an integer n (1<=n<=200, and n is odd) at first. Following that, n positive integers will be given in a line. These numbers indicate the card numbers of the presents.n = 0 ends the input.

 

Output

For each case, output an integer in a line, which is the card number of your present.

 

Sample Input

51 1 3 2 231 2 10

 

Sample Output

32
异或解法
#include <iostream>#include<math.h>using namespace std;int main(void){   int n;   while(cin>>n,n!=0)   {   int m,s=0;   for(int i=0;i<n;i++)   {   cin>>m;   s=s^m;}cout<<s<<endl;   }   return 0;}
MAP解法
 #include <iostream>#include<math.h>#include<algorithm>#include<memory.h>#include<map>using namespace std;int main(){  int n;  while(cin>>n,n!=0)  {  map<int,int>m;  int k;  for(int i=0;i<n;i++)  {   cin>>k;m[k]++;    }    map<int,int>::iterator i;    for(i=m.begin();i!=m.end();i++)    {    if(i->second==1)    cout<<i->first<<endl;}  }  return 0;}