#include "simurgh.h"
#include <bits/stdc++.h>
#define pb push_back
#define f first
#define sc second
using namespace std;
typedef long long int ll;
typedef string str;
struct dsu{
int n;
vector<int> sz, p;
dsu(int _n): n(_n){
sz.resize(n, 1);
p.resize(n);
for(int i = 0; i < n; i++) p[i] = i;
}
int get(int x){
if(p[x] != x) p[x] = get(p[x]);
return p[x];
}
bool unite(int a, int b){
a = get(a), b = get(b);
if(a == b) return 0;
if(sz[b] > sz[a]) swap(a, b);
sz[a]+=sz[b];
sz[b] = 0;
p[b] = a;
return 1;
}
};
int n, m;
vector<int> U, V;
vector<int> royal;
vector<vector<pair<int, int>>> graph;
int count_common_roads(basic_string<int> E){
vector<int> EE;
for(int x: E) EE.pb(x);
return count_common_roads(EE);
}
basic_string<int> generate_tree(basic_string<int> E){
dsu ds(n);
basic_string<int> T;
for(int i: E){
if(ds.unite(U[i], V[i])) T.pb(i);
else return {};
}
for(int i = 0; i < m; i++) if(ds.unite(U[i], V[i])) T.pb(i);
return T;
}
int replacement_edge(basic_string<int> E, int i){
dsu ds(n);
for(int j: E) if(j != i) ds.unite(U[j], V[j]);
for(int j = 0; j < m; j++) if(j != i && ds.unite(U[j], V[j])) return j;
return -1;
}
int count_extra_royal(basic_string<int> T, basic_string<int> C){
dsu ds(n);
int c = 0;
vector<int> q;
for(int i: C) ds.unite(U[i], V[i]), q.pb(i);
for(int i: T) if(ds.unite(U[i], V[i])) c+=max(royal[i], 0), q.pb(i);
return count_common_roads(q)-c;
}
vector<int> find_roads(int _n, vector<int> _U, vector<int> _V){
swap(n, _n), swap(U, _U), swap(V, _V);
m = U.size();
royal.assign(m, -1);
graph.resize(n);
for(int i = 0; i < m; i++){
graph[U[i]].pb({V[i], i});
graph[V[i]].pb({U[i], i});
}
basic_string<int> A, B = {0};
while(1){
int x, y;
int ei = int(A.size()+B.size())-1, e = B.back();
if(A.size()+B.size() == n-1){
int cnt = 0;
for(int i: A) if(royal[i] == 1) cnt++;
int x = count_common_roads(A+B);
A+=B;
for(int i: B) royal[i] = (x > cnt);
break;
}
auto T = generate_tree(A+B);
int i = replacement_edge(T, e);
if(i == -1){
for(int j: B) royal[j] = 1;
goto finalize;
}
x = count_common_roads(T);
T[ei] = i;
y = count_common_roads(T);
T[ei] = e;
if(x > y){
for(int j: B) royal[j] = 1;
royal[i] = 0;
goto finalize;
}
else if(x < y){
for(int j: B) royal[j] = 0;
royal[i] = 1;
goto finalize;
}
else{
if(royal[i] != -1){
for(int j: B) royal[j] = royal[i];
goto finalize;
}
auto T2 = generate_tree(A+B+i);
if(T2.empty()){
for(int j: B) royal[j] = 0;
royal[i] = 0;
goto finalize;
}
else{
B.pb(i);
continue;
}
}
finalize:
A+=B;
B.clear();
if(A.size() + B.size() == n-1) break;
B+=T[A.size()+B.size()];
}
vector<int> ans;
for(int i = 0; i < m; i++) if(royal[i] == 1) ans.pb(i);
for(int nd = 0; nd < n; nd++){
basic_string<int> S;
for(auto [x, i]: graph[nd]) if(royal[i] == -1) S.pb(i);
if(S.empty()) continue;
int X = count_extra_royal(A, S);
while(X > 0){
int a = 0, b = int(S.size())-1;
while(a < b){
basic_string<int> s;
int md = (a+b)/2;
for(int j = 0; j <= md; j++) s.pb(S[j]);
int x = count_extra_royal(A, s);
if(x >= X) b = md;
else a = md+1;
}
royal[S[a]] = 1;
ans.pb(S[a]);
X--;
}
for(int i: S) if(royal[i] == -1) royal[i] = 0;
}
return ans;
}
Compilation message
simurgh.cpp: In function 'std::vector<int> find_roads(int, std::vector<int>, std::vector<int>)':
simurgh.cpp:84:30: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
84 | if(A.size()+B.size() == n-1){
| ~~~~~~~~~~~~~~~~~~^~~~~~
simurgh.cpp:135:32: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
135 | if(A.size() + B.size() == n-1) break;
| ~~~~~~~~~~~~~~~~~~~~^~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
212 KB |
correct |
| 2 |
Correct |
1 ms |
212 KB |
correct |
| 3 |
Correct |
1 ms |
212 KB |
correct |
| 4 |
Incorrect |
1 ms |
212 KB |
WA in grader: NO |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
212 KB |
correct |
| 2 |
Correct |
1 ms |
212 KB |
correct |
| 3 |
Correct |
1 ms |
212 KB |
correct |
| 4 |
Incorrect |
1 ms |
212 KB |
WA in grader: NO |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
212 KB |
correct |
| 2 |
Correct |
1 ms |
212 KB |
correct |
| 3 |
Correct |
1 ms |
212 KB |
correct |
| 4 |
Incorrect |
1 ms |
212 KB |
WA in grader: NO |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
212 KB |
correct |
| 2 |
Correct |
1 ms |
212 KB |
correct |
| 3 |
Correct |
511 ms |
4312 KB |
correct |
| 4 |
Correct |
938 ms |
6092 KB |
correct |
| 5 |
Correct |
940 ms |
6092 KB |
correct |
| 6 |
Correct |
927 ms |
6096 KB |
correct |
| 7 |
Correct |
940 ms |
6092 KB |
correct |
| 8 |
Correct |
941 ms |
5996 KB |
correct |
| 9 |
Correct |
934 ms |
5996 KB |
correct |
| 10 |
Correct |
929 ms |
5964 KB |
correct |
| 11 |
Correct |
919 ms |
5996 KB |
correct |
| 12 |
Correct |
931 ms |
5996 KB |
correct |
| 13 |
Correct |
1 ms |
212 KB |
correct |
| 14 |
Correct |
918 ms |
5952 KB |
correct |
| 15 |
Correct |
940 ms |
5972 KB |
correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
212 KB |
correct |
| 2 |
Correct |
1 ms |
212 KB |
correct |
| 3 |
Correct |
1 ms |
212 KB |
correct |
| 4 |
Incorrect |
1 ms |
212 KB |
WA in grader: NO |
| 5 |
Halted |
0 ms |
0 KB |
- |
