#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 = 505, MAX_M = MAX_N * MAX_N;
#include "simurgh.h"
int qry(const vector<int> &r) { return count_common_roads(r); }
struct dsu {
vector<int> g, sz;
dsu (int n) { g.resize(n+10), sz.resize(n+10, 1), iota(AI(g), 0); }
int F(int i) { return i == g[i] ? i : g[i] = F(g[i]); }
int S(int i) { return sz[ F(i) ]; }
bool M(int a, int b) {
a = F(a), b = F(b);
if (a == b) return false;
if (sz[a] < sz[b]) swap(a, b);
return sz[a] += sz[b], g[b] = a, true;
}
};
int id[MAX_N][MAX_N], m, n;
bool isin[MAX_N][MAX_N], is1[MAX_N][MAX_N];
struct tree {
vector<pair<int,int>> alle;
vector<int> get_cycle(int a, int b) {
vector<vector<int>> edge(n);
for (auto [a, b] : alle)
edge[a].pb(b), edge[b].pb(a);
vector<int> res, stk;
function<bool(int,int)> dfs = [&](int x, int lst) {
stk.pb(x);
if (x == b) {
res = stk;
return true;
}
for (int u : edge[x]) if (u != lst) {
if (dfs(u, x)) return true;
}
stk.pop_back();
return false;
};
dfs(a, a);
return res;
}
void remove(int a, int b) {
if (a > b) swap(a, b);
alle.erase(find(AI(alle), make_pair(a, b)));
}
void add_edge(int a, int b) { if (a > b) swap(a, b); alle.pb(a, b); }
};
vector<int> operator - (vector<int> a, int b) { a.erase(find(AI(a), b)); return a; }
vector<int> to_id(vector<pair<int,int>> a) { vector<int> b; for (auto [x, y] : a) b.pb(id[x][y]); return b; }
vector<int> operator + (vector<int> a, int b) { a.pb(b); return a; }
std::vector<int> find_roads(int n, std::vector<int> u, std::vector<int> v) {
::n = n;
m = u.size();
vector<pair<int,int>> alle(m);
for (int i = 0;i < m;++i) {
id[v[i]][u[i]] = id[u[i]][v[i]] = i;
alle[i] = {u[i], v[i]};
}
// I need to find a tree
vector<pair<int,int>> out, bad;
tree T;
{
dsu D(n);
for (auto [a, b] : alle) {
if (D.M(a, b))
T.add_edge(a, b);
else
out.pb(a, b);
}
}
dsu allz(n);
auto upd = [&](int a, int b) {
if (allz.M(a, b)) {
bad.pb(a, b);
isin[a][b] = isin[b][a] = true;
}
};
// then I want to find a forest which has all 0
for (auto [a, b] : out) {
if (allz.F(a) == allz.F(b)) continue;
auto cir = T.get_cycle(a, b);
vector<int> tall;
for (auto [x, y] : T.alle)
tall.pb(id[x][y]);
if (tall.size() == 2) continue;
int old = qry(tall);
for (int i = 1;i < cir.size();++i) {
int x = cir[i-1], y = cir[i];
int val = qry(tall - id[x][y] + id[a][b]);
if (val < old)
break;
if (val > old) {
T.remove(x, y);
T.add_edge(a, b);
a = x, b = y;
break;
}
}
upd(a, b);
}
// then I need to put the bridges back to both ANS, and BAD
dsu G(n);
vector<int> ans;
// cnt_bridges
int cnt_b = n-1 - bad.size();
for (auto [a, b] : T.alle)
if (allz.M(a, b)) {
bad.pb(a, b);
ans.pb(id[a][b]);
isin[a][b] = isin[b][a] = true;
G.M(a, b);
is1[b][a] = is1[a][b] = true;
}
DE(cnt_b, qry(to_id(bad)), ans.size());
while (alle.size()) {
DE(alle.size());
dsu D(n);
vector<pair<int,int>> now;
int sz = 0;
for (auto [a, b] : alle) {
if (!isin[a][b] && G.F(a) != G.F(b)) {
if (D.M(a, b))
now.pb(a, b);
else alle[sz++] = {a, b};
}
}
alle.resize(sz);
int osz = now.size(), cnt_b = 0;
DE(osz);
for (auto [a, b] : bad)
if (D.M(a, b)) {
now.pb(a, b);
cnt_b += is1[a][b];
}
int val = qry(to_id(now));
if (val == cnt_b) continue;
for (int i = cnt_b + 1;i <= val;++i) {
int l = 0, r = n-cnt_b, m;
while (l < r) {
m = l + r >> 1;
vector<pair<int,int>> q;
dsu D(n);
for (int j = 0;j <= m;++j) {
D.M(now[j].first, now[j].second);
q.pb(now[j]);
}
for (auto [a, b] : bad)
if (D.M(a, b))
q.pb(a, b);
if (qry(to_id(q)) >= i)
r = m;
else
l = m+1;
}
auto [a, b] = now[l];
ans.pb(id[a][b]);
DE(a, b);
G.M(a, b);
}
}
return ans;
}
Compilation message
simurgh.cpp: In function 'std::vector<int> find_roads(int, std::vector<int>, std::vector<int>)':
simurgh.cpp:119:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
119 | for (int i = 1;i < cir.size();++i) {
| ~~^~~~~~~~~~~~
simurgh.cpp:14:17: warning: statement has no effect [-Wunused-value]
14 | #define DE(...) 0
| ^
simurgh.cpp:155:2: note: in expansion of macro 'DE'
155 | DE(cnt_b, qry(to_id(bad)), ans.size());
| ^~
simurgh.cpp:14:17: warning: statement has no effect [-Wunused-value]
14 | #define DE(...) 0
| ^
simurgh.cpp:159:3: note: in expansion of macro 'DE'
159 | DE(alle.size());
| ^~
simurgh.cpp:14:17: warning: statement has no effect [-Wunused-value]
14 | #define DE(...) 0
| ^
simurgh.cpp:172:3: note: in expansion of macro 'DE'
172 | DE(osz);
| ^~
simurgh.cpp:185:11: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
185 | m = l + r >> 1;
| ~~^~~
simurgh.cpp:14:17: warning: statement has no effect [-Wunused-value]
14 | #define DE(...) 0
| ^
simurgh.cpp:203:3: note: in expansion of macro 'DE'
203 | DE(a, b);
| ^~
simurgh.cpp:171:7: warning: unused variable 'osz' [-Wunused-variable]
171 | int osz = now.size(), cnt_b = 0;
| ^~~
simurgh.cpp:144:6: warning: unused variable 'cnt_b' [-Wunused-variable]
144 | int cnt_b = n-1 - bad.size();
| ^~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
204 KB |
WA in grader: NO |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
204 KB |
WA in grader: NO |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
204 KB |
WA in grader: NO |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
204 KB |
correct |
| 2 |
Correct |
1 ms |
332 KB |
correct |
| 3 |
Correct |
451 ms |
4120 KB |
correct |
| 4 |
Runtime error |
280 ms |
11092 KB |
Execution killed with signal 11 |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
204 KB |
WA in grader: NO |
| 2 |
Halted |
0 ms |
0 KB |
- |
