原题:http://acm.hdu.edu.cn/showproblem.php?pid=2095
参考:http://acm.hdu.edu.cn/showproblem.php?pid=2095
为啥人家用map就过了,我用map就超时
scanf比cin的实时性好,要用scanf
#include <iostream>
#include <string>
#include <map>
using namespace std;
int main()
{
int n;
map<int,int> m1;
while(scanf("%d",&n) && n)
{
m1.clear();
int b;
while(n--)
{
scanf("%d",&b);
m1[b]++;
}
map<int, int>::iterator iter;
for(iter=m1.begin(); iter!=m1.end(); iter++)
{
if(iter->second == 1)
{
cout<<iter->first<<endl;
break;
}
}
}
return 0;
}