博弈论入门题 kiki's game

#include<iostream>
#include<cstdio>
#include<cmath>
#include<cstring>
#include<sstream>
#include<algorithm>
#include<queue>
#include<deque>
#include<iomanip>
#include<vector>
#include<cmath>
#include<map>
#include<stack>
#include<set>
#include<functional>
#include<fstream>
#include<memory>
#include<list>
#include<string>
using namespace std;
typedef long long LL;
typedef unsigned long long ULL;

#define N 100
#define MAXN 20000 + 9
#define INF 1000000009
#define eps 0.00000001
#define sf(a) scanf("%d",&a)

int n;
int a[N];
int main()
{
    while (sf(n), n)
    {
        int sum = 0;
        for (int i = 0; i < n; i++)
            sf(a[i]), sum ^= a[i];
        if (sum == 0)
            cout << 0 << endl;
        else
        {
            int ans = 0;
            for (int i = 0; i < n; i++)
            {
                if ((sum^a[i]) < a[i])
                    ans++;
            }
            cout << ans << endl;
        }
    }
}