#pragma GCC optimization("03")
#pragma GCC optimization("unroll-loops")
#pragma comment(linker, "/stack:200000000")
#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popused,abm,mmx,avx,tune=native")
#include<bits/stdc++.h>
using namespace std;
const int N = 3 * 1e5 + 5;
const long long inf = 1000000000;
#define ll long long
#define F first
#define S second
#define pb push_back
int n, x[N];
map<int, bool> used;
map<int, int> cnt;
vector<int> v;
long long res, f;
main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
cin >> n;
for(int i = 1; i <= n; ++i){
cin >> x[i];
used[x[i]] = !used[x[i]];
cnt[x[i]]++;
}
for(int i = 1; i <= n; ++i){
if(cnt[x[i]]) {
f = cnt[x[i]];
if(f * (f - 1) / 2 % 2 == 1) res ^= x[i] + x[i];
cnt[x[i]] = 0;
}
if(used[x[i]]) {
v.pb(x[i]);
used[x[i]] = 0;
}
}
for(int i = 0; i < v.size(); ++i){
for(int j = i; j < v.size(); ++j){
res ^= v[i] + v[j];
}
}
cout << res;
}
Compilation message
xorsum.cpp:1: warning: ignoring '#pragma GCC optimization' [-Wunknown-pragmas]
1 | #pragma GCC optimization("03")
|
xorsum.cpp:2: warning: ignoring '#pragma GCC optimization' [-Wunknown-pragmas]
2 | #pragma GCC optimization("unroll-loops")
|
xorsum.cpp:3: warning: ignoring '#pragma comment ' [-Wunknown-pragmas]
3 | #pragma comment(linker, "/stack:200000000")
|
cc1plus: error: attribute 'popused' argument 'target' is unknown
xorsum.cpp:24:2: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
24 | main() {
| ^~~~
xorsum.cpp: In function 'int main()':
xorsum.cpp:50:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
50 | for(int i = 0; i < v.size(); ++i){
| ~~^~~~~~~~~~
xorsum.cpp:51:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
51 | for(int j = i; j < v.size(); ++j){
| ~~^~~~~~~~~~
