#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define pb emplace_back
#define AI(i) begin(i), end(i)
template<class T> bool chmin(T &a, T b) { return b < a && (a = b, true); }
template<class T> bool chmax(T &a, T b) { return a < b && (a = b, true); }
#ifdef KEV
#define DE(args...) kout("[ " + string(#args) + " ] = ", args)
void kout() { cerr << endl; }
template<class T, class ...U> void kout(T a, U ...b) { cerr << a << ' ', kout(b...); }
template<class T> void debug(T l, T r) { while (l != r) cerr << *l << " \n"[next(l)==r], ++l; }
#else
#define DE(...) 0
#define debug(...) 0
#endif
const int MAX_N = 1000010, MAX_B = 35;
#define int ll
int n, a[MAX_N], cnt[MAX_B];
ll sum(ll l, ll r) { return (l + r) * (r - l + 1) / 2; }
int32_t main() {
ios_base::sync_with_stdio(0), cin.tie(0);
cin >> n;
for (int i = 0;i < n;++i)
cin >> a[i];
sort(a, a + n);
for (int b = 30;b >= 0;--b) {
if (~a[n-1]>>b&1) continue;
int M = 0;
while (M < n && (~a[M]>>b&1)) ++M;
debug(a, a + n);
for (int i = M;i < n;++i) a[i] ^= 1ll<<b;
ll val = 1ll << b;
ll x = 0;
for (int i = 0, j = n-1;i < M;++i) {
while (j >= M && a[i] + a[j] >= val)
--j;
x += j - M + 1;
}
// 0s, 1s
ll A = M, B = n - M;
cnt[b + 1] ^= (sum(1, B)) + A * B - x;
cnt[b] ^= (A * B);
inplace_merge(a, a + M, a + n);
}
int res = 0;
for (int i = 0;i <= 30;++i) if (cnt[i] & 1) {
res |= 1ll << i;
}
cout << res << '\n';
}
Compilation message
xorsum.cpp: In function 'int32_t main()':
xorsum.cpp:15:20: warning: statement has no effect [-Wunused-value]
15 | #define debug(...) 0
| ^
xorsum.cpp:39:3: note: in expansion of macro 'debug'
39 | debug(a, a + n);
| ^~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
332 KB |
Output is correct |
2 |
Correct |
2 ms |
332 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
193 ms |
12000 KB |
Output is correct |
2 |
Correct |
179 ms |
11244 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
193 ms |
12000 KB |
Output is correct |
2 |
Correct |
179 ms |
11244 KB |
Output is correct |
3 |
Correct |
293 ms |
12168 KB |
Output is correct |
4 |
Correct |
299 ms |
11580 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
332 KB |
Output is correct |
2 |
Correct |
2 ms |
332 KB |
Output is correct |
3 |
Correct |
43 ms |
1424 KB |
Output is correct |
4 |
Correct |
44 ms |
1512 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
332 KB |
Output is correct |
2 |
Correct |
2 ms |
332 KB |
Output is correct |
3 |
Correct |
193 ms |
12000 KB |
Output is correct |
4 |
Correct |
179 ms |
11244 KB |
Output is correct |
5 |
Correct |
293 ms |
12168 KB |
Output is correct |
6 |
Correct |
299 ms |
11580 KB |
Output is correct |
7 |
Correct |
43 ms |
1424 KB |
Output is correct |
8 |
Correct |
44 ms |
1512 KB |
Output is correct |
9 |
Correct |
430 ms |
12020 KB |
Output is correct |
10 |
Correct |
422 ms |
12044 KB |
Output is correct |
11 |
Correct |
419 ms |
11964 KB |
Output is correct |