#include <bits/stdc++.h>
#include <ostream>
#define pb push_back
#define s second
#define f first
#define pb push_back
#define pii pair <int,int>
#define ll long long
#define left h*2,l,(l + r)/2
#define right h*2+1,(l + r)/2 + 1,r
#define int ll
using namespace std;
const int N = 1e6 + 5,inf = 1e9;
int a[N];
pii arr[N],b[N];
bool fix[N];
signed main() {
ios_base::sync_with_stdio(0),cin.tie(NULL),cout.tie(NULL);
int n;
cin>>n;
for (int i = 1; i <= n; i++){
cin >> a[i];
}
for (int j = 1; j <= n; j++)
arr[j] = {(a[j] & ((1<<(0 + 1)) - 1)),j};
sort(arr+1,arr+n+1);
int ans=0,add=0;
for (int i = 0; i <= 30; i++){
int m = n;
for (int j = 1; j <= n; j++){
int bb = ((a[arr[j].s] >> i) & 1);
if(bb > 0) fix[j] = 1,arr[++m] = arr[j];
}
int idx = 0;
for (int j = 1; j <= m; j++){
if (fix[j]) continue;
b[++idx] = arr[j];
}
for (int j = 1; j <= n; j++){
int x = b[j].s;
arr[j] = {(a[x] & ((1<<(i + 1)) - 1)),x};
fix[j] = 0;
}
vector <pair <pii,int> > v;
for (int j = 1; j <= n; j++){
int sum = ((arr[j].f + arr[n].f) >> i) & 3;
if (v.size() && v.back().s == sum) v.back().f.s += 1;
else {
v.pb({{j,j},sum});
}
}
int cnt = 0,add = 0;
/*
for (int j = n; j >= 1; j--){
vector <pair<pii,int> > vnew;
for (int k = 0; k < v.size(); k++){
int l = v[k].f.f,r = v[k].f.s,val = v[k].s;
while (r + 1 <= n){
int sum = (((arr[r + 1].f + arr[j].f) >> i) & 3);
if (sum == val) r += 1;
else break;
}
while (l <= n){
int sum = (((arr[l].f + arr[j].f) >> i) & 3);
if (sum != val) l += 1;
else break;
}
if (l <= r){
vnew.pb({{l,r},val});
}
}
sort(vnew.begin(),vnew.end());
int id = 1,k = 0;
vector <pair<pii,int> > vec;
while (k < vnew.size()){
if (id == vnew[k].f.f){
vec.pb(vnew[k]);
id = vnew[k].f.s + 1;
k++;
}else{
int l = id,r = id,val = (((arr[id].f + arr[j].f) >> i) & 3);
while (r + 1 <= n){
int sum = (((arr[r + 1].f + arr[j].f) >> i) & 3);
if (sum == val) r += 1;
else break;
}
vec.pb({{l,r},val});
id = r + 1;
}
}
sort(vec.begin(),vec.end());
for (int k = 0; k <vec.size(); k++){
int s = vec[k].s;
if (s == 3 || s == 1){
int l = vec[k].f.f,r = vec[k].f.s;
l = max(l,j);
cnt += max(0LL,(r - l + 1));
}
}
v = vec;
}*/
if (cnt & 1) ans |= (1LL<<i);
}
cout<<ans;
}
Compilation message
xorsum.cpp: In function 'int main()':
xorsum.cpp:62:17: warning: unused variable 'add' [-Wunused-variable]
62 | int cnt = 0,add = 0;
| ^~~
xorsum.cpp:33:13: warning: unused variable 'add' [-Wunused-variable]
33 | int ans=0,add=0;
| ^~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
3 ms |
6492 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
348 ms |
45624 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
348 ms |
45624 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
3 ms |
6492 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
3 ms |
6492 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |