QOJ.ac
QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#218272 | #6555. Sets May Be Good | zhaohaikun | WA | 0ms | 3708kb | C++14 | 2.6kb | 2023-10-17 22:08:28 | 2023-10-17 22:08:28 |
Judging History
answer
// MagicDark
#include <bits/stdc++.h>
#define debug cerr << "[" << __LINE__ << "] "
#define SZ(x) (int) x.size() - 1
#define all(x) x.begin(), x.end()
#define ms(x, y) memset(x, y, sizeof x)
#define F(i, x, y) for (int i = (x); i <= (y); i++)
#define DF(i, x, y) for (int i = (x); i >= (y); i--)
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
template <typename T> inline void chkmax(T& x, T y) { x = max(x, y); }
template <typename T> inline void chkmin(T& x, T y) { x = min(x, y); }
template <typename T> inline void read(T &x) {
x = 0; int f = 1; char c = getchar();
for (; !isdigit(c); c = getchar()) if (c == '-') f = -f;
for (; isdigit(c); c = getchar()) x = (x << 1) + (x << 3) + (c ^ 48);
x *= f;
}
const int N = 1010, MOD = 998244353, inv2 = (MOD + 1) >> 1;
int n, m, ans = 1, t = 1;
bitset <N> a[N];
signed main() {
read(n), read(m);
F(i, 1, n) t = 2 * t % MOD;
F(i, 1, m) {
int x, y; read(x), read(y);
a[x][y] = a[y][x] = true;
}
DF(i, n, 1) {
// F(x, 1, i) {
// F(y, 1, i)
// cout << a[x][y];
// cout << endl;
// }
// cout << endl;
bool flag = false;
F(j, 1, i - 1) flag |= a[i][j];
if (flag) {
int pos;
F(j, 1, i - 1)
if (a[j][i]) {
pos = j;
break;
}
// F(j, 1, i - 1)
// if (a[i][i] && a[i][j] && j != pos) a[j][j].flip();
// F(x, 1, i) {
// F(y, 1, i)
// cout << a[x][y];
// cout << endl;
// }
// cout << endl;
// debug << pos << endl;
a[i][pos] = false;
F(j, 1, i - 1) if (j != pos && a[pos][j]) {
a[j] ^= a[i];
if (a[i][i] ^ a[i][j]) a[j][j].flip();
}
F(j, 1, i - 1) if (j != pos && a[i][j]) {
a[j] ^= a[pos];
}
if (a[pos][pos]) {
F(j, 1, n)
if (j != i && j != pos && a[i][j]) a[j][j].flip();
if (a[i][i]) ans = (ll) ans * (MOD - 1) % MOD;//, debug << "FUCK\n";
}
// F(x, 1, i) {
// F(y, 1, i)
// cout << a[x][y];
// cout << endl;
// }
// cout << pos << endl;
// debug << i << " " << pos << endl;
F(j, 1, i - 2) {
if (j >= pos) a[j] = a[j + 1];
bitset <N> s = (a[j] >> pos) << pos;
// F(k, 1, i - 1) cout << a[j][k]; cout << endl;
a[j] = a[j] ^ s ^ (s >> 1);
// F(k, 1, i - 2) cout << a[j][k]; cout << endl;
}
i--;
ans = (ll) ans * 2 % MOD;
// debug << i << endl;
} else if (!a[i][i]) ans = (ll) ans * 2 % MOD;//, debug << i << endl;
else ans = 0;
}
// debug << ans << endl;
cout << (ll) (t + ans) * inv2 % MOD;
return 0;
}
/* why?
4 6
1 2
1 3
1 4
2 3
2 4
3 4
*/
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 0ms
memory: 3644kb
input:
5 5 1 2 2 3 3 4 4 5 1 5
output:
16
result:
ok 1 number(s): "16"
Test #2:
score: 0
Accepted
time: 0ms
memory: 3580kb
input:
3 0
output:
8
result:
ok 1 number(s): "8"
Test #3:
score: 0
Accepted
time: 0ms
memory: 3656kb
input:
2 1 1 2
output:
3
result:
ok 1 number(s): "3"
Test #4:
score: 0
Accepted
time: 0ms
memory: 3572kb
input:
4 6 1 2 1 3 1 4 2 3 2 4 3 4
output:
6
result:
ok 1 number(s): "6"
Test #5:
score: 0
Accepted
time: 0ms
memory: 3708kb
input:
1 0
output:
2
result:
ok 1 number(s): "2"
Test #6:
score: 0
Accepted
time: 0ms
memory: 3580kb
input:
4 5 1 2 1 3 1 4 2 3 3 4
output:
8
result:
ok 1 number(s): "8"
Test #7:
score: 0
Accepted
time: 0ms
memory: 3580kb
input:
5 3 1 3 1 4 1 5
output:
24
result:
ok 1 number(s): "24"
Test #8:
score: 0
Accepted
time: 0ms
memory: 3656kb
input:
5 0
output:
32
result:
ok 1 number(s): "32"
Test #9:
score: 0
Accepted
time: 0ms
memory: 3616kb
input:
6 3 1 2 3 4 3 6
output:
40
result:
ok 1 number(s): "40"
Test #10:
score: 0
Accepted
time: 0ms
memory: 3644kb
input:
6 0
output:
64
result:
ok 1 number(s): "64"
Test #11:
score: 0
Accepted
time: 0ms
memory: 3668kb
input:
7 3 2 3 3 6 6 7
output:
80
result:
ok 1 number(s): "80"
Test #12:
score: 0
Accepted
time: 0ms
memory: 3524kb
input:
7 0
output:
128
result:
ok 1 number(s): "128"
Test #13:
score: -100
Wrong Answer
time: 0ms
memory: 3640kb
input:
20 30 1 7 1 9 1 12 1 13 2 6 2 17 3 13 4 12 4 15 4 17 6 10 6 17 7 8 7 18 8 14 9 13 10 16 10 17 12 14 13 15 13 16 13 20 14 16 14 18 14 20 15 17 15 18 15 19 15 20 16 17
output:
525312
result:
wrong answer 1st numbers differ - expected: '524288', found: '525312'