HDU 1563 Find your present!

 

http://acm.hdu.edu.cn/showproblem.php?pid=1563

找只出现一次的数，排个序处理下就行

View Code

#include <iostream>
#include <algorithm>
using namespace std ;
int main()
{
    int n;
    while(scanf("%d",&n),n)
    {
        int a[201];
        a[1]=a[n+1]=-1;
        for(int i=1;i<=n;i++)
            scanf("%d",&a[i]);
        sort(a+1,a+1+n);
        for(int i=1;i<=n;i++)
            if(a[i]!=a[i-1]&&a[i]!=a[i+1])
            {
                printf("%d\n",a[i]);
                break;
            }
    }
    return 0;
}