// Om Namah Shivaya
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x, y) ((x + y - 1) / (y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl
#define rep(i, n) for(int i = 0; i < n; ++i)
#define rep1(i, n) for(int i = 1; i <= n; ++i)
#define rev(i, s, e) for(int i = s; i >= e; --i)
#define trav(i, a) for(auto &i : a)
template<typename T>
void amin(T &a, T b) {
a = min(a, b);
}
template<typename T>
void amax(T &a, T b) {
a = max(a, b);
}
#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif
/*
*/
const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;
void solve(int test_case)
{
int n; cin >> n;
vector<int> a(n);
rep(i,n) cin >> a[i];
int mx = *max_element(all(a));
vector<int> b(n);
auto get = [&](int l, int r){
return upper_bound(all(b),r) - lower_bound(all(b),l);
};
int ans = 0;
vector<int> cnt(1<<25);
for(int f = 1; f <= 2*mx; f <<= 1){
if((f<<1) < (1<<25)){
rep(i,f<<1){
cnt[i] = 0;
}
rep(i,n){
int v = a[i]%(f<<1);
cnt[v]++;
}
int ptr = 0;
rep(i,f<<1){
int c = cnt[i];
rep(j,c){
b[ptr++] = i;
}
}
if(ptr != n){
exit(1);
}
}
else{
rep(i,n) b[i] = a[i]%(f<<1);
sort(all(b));
}
int ptr1 = n-1, ptr2 = n-1, ptr3 = n-1;
ll cnt1 = 0, cnt2 = 0;
rep(i,n){
int x = b[i];
while(ptr1 >= 0 and x+b[ptr1] >= f){
ptr1--;
}
while(ptr2 >= 0 and x+b[ptr2] >= (f<<1)){
ptr2--;
}
while(ptr3 >= 0 and x+b[ptr3] >= 3*f){
ptr3--;
}
int lx = ptr1+1;
int rx = ptr2;
cnt1 += max(rx-lx+1,0);
cnt1 += n-1-ptr3;
if((x+x)&f){
cnt1--;
cnt2++;
}
}
assert(!(cnt1&1));
ll cnt = (cnt1>>1)+cnt2;
ans += (cnt&1)*f;
}
cout << ans << endl;
}
int main()
{
fastio;
int t = 1;
// cin >> t;
rep1(i, t) {
solve(i);
}
return 0;
}
Compilation message
xorsum.cpp: In function 'void solve(int)':
xorsum.cpp:71:10: warning: variable 'get' set but not used [-Wunused-but-set-variable]
71 | auto get = [&](int l, int r){
| ^~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
54 ms |
131072 KB |
Execution killed with signal 9 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
113 ms |
131072 KB |
Execution killed with signal 9 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
113 ms |
131072 KB |
Execution killed with signal 9 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
54 ms |
131072 KB |
Execution killed with signal 9 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
54 ms |
131072 KB |
Execution killed with signal 9 |
2 |
Halted |
0 ms |
0 KB |
- |