#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<ll> vll;
typedef vector<vll> vvll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int, int> pi;
typedef pair<ll, ll> pll;
typedef vector<pi> vpi;
typedef vector<pll> vpll;
typedef vector<vpi> vvpi;
typedef vector<vpll> vvpll;
typedef vector<bool> vb;
#define IOS ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);
#define L(varll, mn, mx) for(ll varll = (mn); varll < (mx); varll++)
#define LR(varll, mx, mn) for(ll varll = (mx); varll > (mn); varll--)
#define LI(vari, mn, mx) for(int vari = (mn); vari < (mx); vari++)
#define LIR(vari, mx, mn) for(int vari = (mx); vari > (mn); vari--)
#define INPV(varvec) for(auto& varveci : (varvec)) cin >> varveci
#define fi first
#define se second
#define pb push_back
#define INF(type) numeric_limits<type>::max()
#define NINF(type) numeric_limits<type>::min()
#define TCASES int t; cin >> t; while(t--)
class UF {
public:
vi par;
vi csize;
int n;
int ncomps;
UF(int a_n): par(a_n, 0), csize(a_n, 1), n(a_n), ncomps(a_n) {
for(int i = 0; i < n; i++) {
par[i] = i;
}
}
int find(int i) {
while(i != par[i]) {
par[i] = par[par[i]];
i = par[i];
}
return i;
}
int conn(int i, int j) {
return find(i) == find(j);
}
void unify(int i, int j) {
int pari = find(i), parj = find(j);
if(pari == parj) return;
if(csize[pari] < csize[parj]) {
par[pari] = parj;
csize[parj] += csize[pari];
} else {
par[parj] = pari;
csize[pari] += csize[parj];
}
ncomps--;
}
};
int N;
vector<int> comps_with_cycle;
bool found_two_cycles = false;
int three_node = -1;
vvi adj;
UF *uf;
vector<UF> ufs;
int ans;
vi crit;
vvi degs;
bool is_crit(int cur_n) {
vb conn(N, false);
for(int j: adj[cur_n]) {
conn[j] = true;
}
int num_1s = 0;
int num_0s = 0;
for(int i = 0; i < N; i++) {
if(i == cur_n) continue;
int sz = adj[i].size();
if(conn[i]) {
sz--;
}
if(sz >= 3) return false;
if(sz == 1) num_1s++;
if(sz == 0) num_0s++;
}
// ! DFS could be optimized
stack<int> st;
vb vis(N, false);
int cid = 0;
for(int s = 0; s < N; s++) {
if(s == cur_n) {
continue;
}
if(!vis[s]) {
st.push(s);
while(!st.empty()) {
int i = st.top();
st.pop();
if(vis[i]) continue;
vis[i] = true;
for(int j : adj[i]) {
if(j == cur_n) continue;
st.push(j);
}
}
cid++;
}
}
return ((num_1s & 0b1) == 0 && (num_1s >> 1) + num_0s == cid);
}
// void upd_neighborhood() {
// neighborhoud_crit.clear();
// for(int i : crit) {
// neighborhoud_crit.insert(i);
// for(int j : adj[i]) {
// neighborhoud_crit.insert(j);
// }
// }
// }
void Init(int N_) {
N = N_;
ans = N;
uf = new UF(N);
for(int i = 0; i < N; i++) {
vi adjr;
adj.pb(adjr);
}
}
void create_ufs_and_degs() {
ufs.clear();
int ind = 0;
for(int i : crit) {
ufs.pb({N});
vi degr(N, 0);
degs.pb(degr);
for(int i1 = 0; i1 < N; i1++) {
if(i1 == i) continue;
for(int i2 : adj[i1]) {
if(i2 == i) continue;
ufs.back().unify(i1, i2);
}
}
for(int i1 = 0; i1 < N; i1++) {
for(int j : adj[i1]) {
if(j == i) continue;
degs[ind][i1]++;
}
}
ind++;
}
}
void Link(int A, int B) {
if(ans == 0) return; // refuse to even process haha
int ncyclecomps = comps_with_cycle.size();
if(ncyclecomps < 2) {
if(ncyclecomps > 0) {
comps_with_cycle[0] = uf->find(comps_with_cycle[0]);
}
if(uf->conn(A, B)) {
// Possible cycle
int poss_cycle_comp = uf->find(A);
if(ncyclecomps == 0 || poss_cycle_comp != comps_with_cycle[0]) comps_with_cycle.pb(poss_cycle_comp);
}
}
ncyclecomps = comps_with_cycle.size();
if(comps_with_cycle.size() == 2) {
ans = 0;
return;
}
bool cycle_made = uf->conn(A, B);
uf->unify(A, B);
adj[A].pb(B);
adj[B].pb(A);
// Check comp sizes
if(three_node == -1) {
if(ncyclecomps == 1) {
ans = uf->csize[uf->find(comps_with_cycle[0])];
}
if(adj[A].size() == 3) three_node = A;
if(adj[B].size() == 3) three_node = B;
// If you find a "three" node, immediately reprocess the graph
// As in, check which ones of the neighbors of the three node are crit
if(three_node != -1) {
if(is_crit(three_node)) crit.pb(three_node);
for(int i : adj[three_node]) {
if(is_crit(i)) crit.pb(i);
}
ans = crit.size();
create_ufs_and_degs();
}
} else {
vi to_remove;
for(int i = 0; i < ans; i++) {
if(A == crit[i] || B == crit[i]) continue;
degs[i][A]++;
degs[i][B]++;
bool made_three = degs[i][A] == 3 || degs[i][B] == 3;
if(ufs[i].conn(A, B) || made_three) {
to_remove.pb(i);
}
ufs[i].unify(A, B);
}
for(int i = to_remove.size() - 1; i >= 0; i--) {
// cout << to_remove[i] << " ";
crit.erase(next(crit.begin(), to_remove[i]));
ufs.erase(next(ufs.begin(), to_remove[i]));
degs.erase(next(degs.begin(), to_remove[i]));
}
// cout << endl;
ans = crit.size();
}
// To simplify casework, idt we need the "four_node" thingy
// if(four_node == -1) {
// if(adj[A].size() == 4) four_node = A;
// if(adj[B].size() == 4) four_node = B;
// // If you find a "four" node, immediately reprocess the graph
// }
}
int CountCritical() {
return ans;
}
Compilation message
rings.cpp: In function 'void Link(int, int)':
rings.cpp:201:10: warning: unused variable 'cycle_made' [-Wunused-variable]
201 | bool cycle_made = uf->conn(A, B);
| ^~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
3 ms |
1056 KB |
Output is correct |
3 |
Correct |
2 ms |
860 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
1 ms |
600 KB |
Output is correct |
6 |
Correct |
1 ms |
860 KB |
Output is correct |
7 |
Correct |
1 ms |
796 KB |
Output is correct |
8 |
Correct |
1 ms |
604 KB |
Output is correct |
9 |
Correct |
3 ms |
1052 KB |
Output is correct |
10 |
Correct |
3 ms |
1052 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
161 ms |
39848 KB |
Output is correct |
2 |
Correct |
725 ms |
92408 KB |
Output is correct |
3 |
Correct |
175 ms |
83884 KB |
Output is correct |
4 |
Correct |
503 ms |
77112 KB |
Output is correct |
5 |
Correct |
480 ms |
76396 KB |
Output is correct |
6 |
Correct |
522 ms |
74612 KB |
Output is correct |
7 |
Correct |
187 ms |
83580 KB |
Output is correct |
8 |
Correct |
1281 ms |
118264 KB |
Output is correct |
9 |
Correct |
1520 ms |
126248 KB |
Output is correct |
10 |
Correct |
346 ms |
74416 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
3 ms |
1056 KB |
Output is correct |
3 |
Correct |
2 ms |
860 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
1 ms |
600 KB |
Output is correct |
6 |
Correct |
1 ms |
860 KB |
Output is correct |
7 |
Correct |
1 ms |
796 KB |
Output is correct |
8 |
Correct |
1 ms |
604 KB |
Output is correct |
9 |
Correct |
3 ms |
1052 KB |
Output is correct |
10 |
Correct |
3 ms |
1052 KB |
Output is correct |
11 |
Correct |
3 ms |
1052 KB |
Output is correct |
12 |
Correct |
4 ms |
1368 KB |
Output is correct |
13 |
Correct |
6 ms |
1548 KB |
Output is correct |
14 |
Correct |
2 ms |
1368 KB |
Output is correct |
15 |
Correct |
3 ms |
2004 KB |
Output is correct |
16 |
Correct |
2 ms |
1112 KB |
Output is correct |
17 |
Correct |
2 ms |
1300 KB |
Output is correct |
18 |
Correct |
3 ms |
2200 KB |
Output is correct |
19 |
Correct |
3 ms |
1080 KB |
Output is correct |
20 |
Correct |
4 ms |
1624 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
3 ms |
1056 KB |
Output is correct |
3 |
Correct |
2 ms |
860 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
1 ms |
600 KB |
Output is correct |
6 |
Correct |
1 ms |
860 KB |
Output is correct |
7 |
Correct |
1 ms |
796 KB |
Output is correct |
8 |
Correct |
1 ms |
604 KB |
Output is correct |
9 |
Correct |
3 ms |
1052 KB |
Output is correct |
10 |
Correct |
3 ms |
1052 KB |
Output is correct |
11 |
Correct |
3 ms |
1052 KB |
Output is correct |
12 |
Correct |
4 ms |
1368 KB |
Output is correct |
13 |
Correct |
6 ms |
1548 KB |
Output is correct |
14 |
Correct |
2 ms |
1368 KB |
Output is correct |
15 |
Correct |
3 ms |
2004 KB |
Output is correct |
16 |
Correct |
2 ms |
1112 KB |
Output is correct |
17 |
Correct |
2 ms |
1300 KB |
Output is correct |
18 |
Correct |
3 ms |
2200 KB |
Output is correct |
19 |
Correct |
3 ms |
1080 KB |
Output is correct |
20 |
Correct |
4 ms |
1624 KB |
Output is correct |
21 |
Correct |
10 ms |
3428 KB |
Output is correct |
22 |
Correct |
18 ms |
4948 KB |
Output is correct |
23 |
Correct |
18 ms |
6344 KB |
Output is correct |
24 |
Correct |
39 ms |
8140 KB |
Output is correct |
25 |
Correct |
11 ms |
9028 KB |
Output is correct |
26 |
Correct |
23 ms |
9168 KB |
Output is correct |
27 |
Correct |
19 ms |
6440 KB |
Output is correct |
28 |
Correct |
15 ms |
7884 KB |
Output is correct |
29 |
Correct |
19 ms |
9892 KB |
Output is correct |
30 |
Correct |
30 ms |
7628 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
3 ms |
1056 KB |
Output is correct |
3 |
Correct |
2 ms |
860 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
1 ms |
600 KB |
Output is correct |
6 |
Correct |
1 ms |
860 KB |
Output is correct |
7 |
Correct |
1 ms |
796 KB |
Output is correct |
8 |
Correct |
1 ms |
604 KB |
Output is correct |
9 |
Correct |
3 ms |
1052 KB |
Output is correct |
10 |
Correct |
3 ms |
1052 KB |
Output is correct |
11 |
Correct |
161 ms |
39848 KB |
Output is correct |
12 |
Correct |
725 ms |
92408 KB |
Output is correct |
13 |
Correct |
175 ms |
83884 KB |
Output is correct |
14 |
Correct |
503 ms |
77112 KB |
Output is correct |
15 |
Correct |
480 ms |
76396 KB |
Output is correct |
16 |
Correct |
522 ms |
74612 KB |
Output is correct |
17 |
Correct |
187 ms |
83580 KB |
Output is correct |
18 |
Correct |
1281 ms |
118264 KB |
Output is correct |
19 |
Correct |
1520 ms |
126248 KB |
Output is correct |
20 |
Correct |
346 ms |
74416 KB |
Output is correct |
21 |
Correct |
3 ms |
1052 KB |
Output is correct |
22 |
Correct |
4 ms |
1368 KB |
Output is correct |
23 |
Correct |
6 ms |
1548 KB |
Output is correct |
24 |
Correct |
2 ms |
1368 KB |
Output is correct |
25 |
Correct |
3 ms |
2004 KB |
Output is correct |
26 |
Correct |
2 ms |
1112 KB |
Output is correct |
27 |
Correct |
2 ms |
1300 KB |
Output is correct |
28 |
Correct |
3 ms |
2200 KB |
Output is correct |
29 |
Correct |
3 ms |
1080 KB |
Output is correct |
30 |
Correct |
4 ms |
1624 KB |
Output is correct |
31 |
Correct |
10 ms |
3428 KB |
Output is correct |
32 |
Correct |
18 ms |
4948 KB |
Output is correct |
33 |
Correct |
18 ms |
6344 KB |
Output is correct |
34 |
Correct |
39 ms |
8140 KB |
Output is correct |
35 |
Correct |
11 ms |
9028 KB |
Output is correct |
36 |
Correct |
23 ms |
9168 KB |
Output is correct |
37 |
Correct |
19 ms |
6440 KB |
Output is correct |
38 |
Correct |
15 ms |
7884 KB |
Output is correct |
39 |
Correct |
19 ms |
9892 KB |
Output is correct |
40 |
Correct |
30 ms |
7628 KB |
Output is correct |
41 |
Correct |
103 ms |
28332 KB |
Output is correct |
42 |
Correct |
509 ms |
89420 KB |
Output is correct |
43 |
Correct |
158 ms |
76872 KB |
Output is correct |
44 |
Correct |
178 ms |
77180 KB |
Output is correct |
45 |
Correct |
303 ms |
94436 KB |
Output is correct |
46 |
Correct |
314 ms |
65192 KB |
Output is correct |
47 |
Correct |
409 ms |
66180 KB |
Output is correct |
48 |
Correct |
173 ms |
83884 KB |
Output is correct |
49 |
Correct |
319 ms |
68020 KB |
Output is correct |
50 |
Correct |
320 ms |
66732 KB |
Output is correct |
51 |
Correct |
177 ms |
66704 KB |
Output is correct |
52 |
Correct |
145 ms |
64936 KB |
Output is correct |
53 |
Correct |
180 ms |
90708 KB |
Output is correct |
54 |
Correct |
967 ms |
98680 KB |
Output is correct |
55 |
Correct |
629 ms |
79492 KB |
Output is correct |