Xor Sum Gym

#include <iostream>#include <cstdio>#include <cstdlib>#include <cstring>#include <cmath>#include <set>#include <stack>#include <queue>#include <ctype.h>#include <vector>#include <algorithm>#include <time.h>// cout << "  ===  " << endl;using namespace std;typedef long long ll;const int maxn = 200000 + 7, INF = 0x3f3f3f3f, mod = 1e9+7;int n;int main() {    scanf("%d", &n);    int ans, x;    cin >> ans;    for(int i = 1; i < n; ++i) {        scanf("%d", &x);        ans = ans^x;    }    printf("%d", ans);    return 0;}