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QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#708719 | #9449. New School Term | Mher777 | WA | 2ms | 9900kb | C++20 | 7.8kb | 2024-11-04 04:31:30 | 2024-11-04 04:31:31 |
Judging History
answer
#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <iomanip>
#include <array>
#include <string>
#include <algorithm>
#include <cmath>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <vector>
#include <stack>
#include <queue>
#include <deque>
#include <bitset>
#include <list>
#include <iterator>
#include <numeric>
#include <complex>
#include <utility>
#include <random>
#include <cassert>
#include <fstream>
using namespace std;
mt19937 rnd(time(nullptr));
/* -------------------- Typedefs -------------------- */
typedef int itn;
typedef long long ll;
typedef unsigned long long ull;
typedef double db;
typedef float fl;
typedef long double ld;
/* -------------------- Usings -------------------- */
using vi = vector<int>;
using vll = vector<ll>;
using mii = map<int, int>;
using mll = map<ll, ll>;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
/* -------------------- Defines -------------------- */
#define ff first
#define ss second
#define pub push_back
#define pob pop_back
#define puf push_front
#define pof pop_front
#define mpr make_pair
#define yes cout<<"Yes\n"
#define no cout<<"No\n"
#define all(x) (x).begin(), (x).end()
#define USACO freopen("feast.in", "r", stdin); freopen("feast.out", "w", stdout);
/* -------------------- Constants -------------------- */
const int dx[8] = { -1, 0, 1, 0, -1, -1, 1, 1 };
const int dy[8] = { 0, -1, 0, 1, -1, 1, -1, 1 };
const int MAX = int(1e9 + 5);
const ll MAXL = ll(1e18) + 5ll;
const ll MOD = ll(1000000007);
const ll MOD2 = ll(998244353);
/* -------------------- Functions -------------------- */
void fastio() {
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
}
void precision(int x) {
cout.setf(ios::fixed | ios::showpoint);
cout.precision(x);
}
ll gcd(ll a, ll b) {
if (a == 0 || b == 0) return(max(a, b));
while (b) {
a %= b;
swap(a, b);
}
return a;
}
ll lcm(ll a, ll b) {
return a / gcd(a, b) * b;
}
ll range_sum(ll a, ll b) {
if (a > b) return 0ll;
ll dif = a - 1, cnt = b - a + 1;
ll ans = ((b - a + 1) * (b - a + 2)) / 2;
ans += ((b - a + 1) * dif);
return ans;
}
string dec_to_bin(ll a) {
string s = "";
for (ll i = a; i > 0; ) {
ll k = i % 2;
i /= 2;
char c = k + 48;
s += c;
}
if (a == 0) {
s = "0";
}
reverse(all(s));
return s;
}
ll bin_to_dec(string s) {
ll num = 0;
for (int i = 0; i < s.size(); i++) {
num *= 2ll;
num += (s[i] - '0');
}
return num;
}
ll factorial_by_mod(ll n, ll mod) {
ll ans = 1;
ll num;
for (ll i = 1; i <= n; ++i) {
num = i % mod;
ans *= num;
ans %= mod;
}
return ans;
}
bool isPrime(ll a) {
if (a == 1) return false;
for (ll i = 2; i * i <= a; i++) {
if (a % i == 0) return false;
}
return true;
}
ll binpow(ll a, ll b) {
if (!a) return 0;
ll ans = 1;
while (b) {
if (b & 1) {
ans *= a;
}
b >>= 1;
a *= a;
}
return ans;
}
ll binpow_by_mod(ll a, ll b, ll mod) {
if (!a) return 0;
ll ans = 1;
while (b) {
if (b & 1) {
ans *= a;
ans %= mod;
}
b >>= 1;
a *= a;
a %= mod;
}
return ans;
}
/* -------------------- Solution -------------------- */
const int N = 100005, M = 1000005;
pii edge[M];
unsigned long long dp[N];
int clr[N], sz[N], p[N], cnt[N][2], used[N], usedd[N], ans[N], dpp[N], from[N];
vi comp[N];
int n, m, last, s, cur_ind;
void add(int x) {
if (!x) return;
for (int i = n; i >= x; --i) {
dp[i] += dp[i - x];
}
}
void del(int x) {
if (!x) return;
for (int i = x; i <= n; ++i) {
dp[i] -= dp[i - x];
}
}
void make_set(int x) {
comp[x] = { x };
cnt[x][0] = 1;
cnt[x][1] = 0;
clr[x] = 0;
sz[x] = 1;
p[x] = x;
}
int find_set(int x) {
if (x == p[x]) return x;
return p[x] = find_set(p[x]);
}
void union_sets(int x, int y, bool f) {
if (sz[x] < sz[y]) swap(x, y);
del(max(cnt[x][0], cnt[x][1]) - min(cnt[x][0], cnt[x][1]));
s -= min(cnt[x][0], cnt[x][1]);
del(max(cnt[y][0], cnt[y][1]) - min(cnt[y][0], cnt[y][1]));
s -= min(cnt[y][0], cnt[y][1]);
if (f) {
swap(cnt[y][0], cnt[y][1]);
}
cnt[x][0] += cnt[y][0];
cnt[x][1] += cnt[y][1];
add(max(cnt[x][0], cnt[x][1]) - min(cnt[x][0], cnt[x][1]));
s += min(cnt[x][0], cnt[x][1]);
if (!dp[n - s]) {
del(max(cnt[x][0], cnt[x][1]) - min(cnt[x][0], cnt[x][1]));
s -= min(cnt[x][0], cnt[x][1]);
cnt[x][0] -= cnt[y][0];
cnt[x][1] -= cnt[y][1];
if (f) {
swap(cnt[y][0], cnt[y][1]);
}
add(max(cnt[x][0], cnt[x][1]) - min(cnt[x][0], cnt[x][1]));
s += min(cnt[x][0], cnt[x][1]);
add(max(cnt[y][0], cnt[y][1]) - min(cnt[y][0], cnt[y][1]));
s += min(cnt[y][0], cnt[y][1]);
return;
}
last = cur_ind;
sz[x] += sz[y];
p[y] = x;
for (auto elem : comp[y]) {
comp[x].pub(elem);
if (f) {
clr[elem] ^= 1;
}
}
}
void slv() {
dp[0] = 1;
cin >> n >> m;
last = m + 1, cur_ind = m;
for (int i = 1; i <= m; ++i) {
cin >> edge[i].ff >> edge[i].ss;
}
for (int i = 1; i <= 2 * n; ++i) {
make_set(i);
add(1);
}
for (int i = m; i >= 1; --i) {
cur_ind = i;
int x = edge[i].ff, y = edge[i].ss;
int x_comp = find_set(x), y_comp = find_set(y);
if (x_comp != y_comp) {
union_sets(x_comp, y_comp, (clr[x] == clr[y]));
continue;
}
if (clr[x] != clr[y] && dp[n - s]) {
last = i;
}
}
vi v;
for (int i = 1; i <= 2 * n; ++i) {
int u = find_set(i);
if (used[u]) continue;
used[u] = 1;
if (cnt[u][0] != cnt[u][1]) {
v.pub(max(cnt[u][0], cnt[u][1]) - min(cnt[u][0], cnt[u][1]));
}
}
dpp[0] = 1;
for (auto elem : v) {
for (int i = n - s; i >= elem; --i) {
if (dpp[i - elem]) {
dpp[i] = 1;
from[i] = elem;
}
}
}
int node = n - s;
while (node) {
++usedd[from[node]];
node -= from[node];
}
for (int i = 1; i <= 2 * n; ++i) {
used[i] = 0;
}
int m1 = 0, m2 = 0;
for (int i = 1; i <= 2 * n; ++i) {
int u = find_set(i);
if (used[u]) continue;
used[u] = 1;
int val = max(cnt[u][0], cnt[u][1]) - min(cnt[u][0], cnt[u][1]), mn = min(cnt[u][0], cnt[u][1]);
m1 += mn, m2 += mn;
if (cnt[u][0] < cnt[u][1]) swap(cnt[u][0], cnt[u][1]);
if (usedd[val]) m1 += val;
else m2 += val;
for (auto elem : comp[u]) {
if (clr[elem] == 0) {
if (usedd[val]) {
ans[elem] = 0;
}
else {
ans[elem] = 1;
}
}
if (clr[elem] == 1) {
if (!usedd[val]) {
ans[elem] = 0;
}
else {
ans[elem] = 1;
}
}
}
if (usedd[val]) --usedd[val];
}
assert(m1 == m2);
for (int i = 1; i <= 2 * n; ++i) {
cout << ans[i];
}
}
void cs() {
int tstc = 1;
//cin >> tstc;
while (tstc--) {
slv();
}
}
void precalc() {
return;
}
int main() {
fastio();
precalc();
//precision(0);
cs();
return 0;
}
Details
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Test #1:
score: 0
Wrong Answer
time: 2ms
memory: 9900kb
input:
2 4 1 3 2 4 1 4 1 2
output:
0111
result:
wrong answer The number of 0s must be equal to that of 1s.