Submission #1114012

#	Time	Username	Problem	Language	Result	Execution time	Memory
1114012		12345678	XOR Sum (info1cup17_xorsum)	C++17	11 / 100	79 ms	14920 KiB

xorsum

#include <bits/stdc++.h>

using namespace std;

const int nx=1e6+5;

int n, a[nx], f[nx], res;

int main()
{
    cin.tie(NULL)->sync_with_stdio(false);
    cin>>n;
    for (int i=1; i<=n; i++) cin>>a[i], f[a[i]]++;
    for (int i=1; i<=4000; i++) for (int j=i+1; j<=4000; j++) if ((f[i]%2)&&(f[j]%2)) res=res^(i+j);
    for (int i=1; i<=4000; i++) if ((f[i]*(f[i]+1)/2)%2) res=(res^(2*i));
    cout<<res;
}

• Subtask 1: 0 / 7
• Subtask 2: 11 / 11
• Subtask 3: 0 / 21
• Subtask 4: 0 / 38
• Subtask 5: 0 / 23