| # |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
| 859813 |
2023-10-10T17:34:57 Z |
aykhn |
Traffic (IOI10_traffic) |
C++14 |
|
7 ms |
37208 KB |
#include "traffic.h"
#include <bits/stdc++.h>
// author: aykhn
using namespace std;
typedef long long ll;
#define TC int t; cin >> t; while (t--) _();
#define OPT ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define all(v) v.begin(), v.end()
#define pii pair<int, int>
#define mpr make_pair
#define eb emplace_back
#define pb push_back
#define ts to_string
#define fi first
#define se second
#define ins insert
#define inf 0x3F3F3F3F
#define infll 0x3F3F3F3F3F3F3F3FLL
#define bpc __builtin_popcount
const int MXN = 1e6 + 5;
int n, sz = 1;
vector<int> st;
vector<pii> adj[MXN];
int used[MXN];
int dist[MXN];
int in[MXN];
int out[MXN];
int tim = -1;
pii mx[MXN];
int ans[MXN];
void make(int lx, int rx, int val, int l, int r, int x)
{
if (l >= rx || r <= lx) return;
if (l >= lx && r <= rx)
{
st[x] = max(st[x], val);
return;
}
int mid = (l + r) >> 1;
make(lx, rx, val, l, mid, 2*x + 1);
make(lx, rx, val, mid, r, 2*x + 2);
}
int get(int ind, int l, int r, int x)
{
if (l + 1 == r) return st[x];
int mid = (l + r) >> 1;
if (ind < mid) return max(st[x], get(ind, l, mid, 2*x + 1));
else return max(st[x], get(ind, mid, r, 2*x + 2));
}
void dfs(int a, int w)
{
in[a] = ++tim;
dist[a] = w;
used[a] = 1;
for (int i = 0; i < adj[a].size(); i++)
{
pii v = adj[a][i];
if (used[v.fi]) continue;
dfs(v.fi, w + v.se);
if (mx[v.fi].fi + v.se > mx[a].fi)
{
mx[a].se = mx[a].fi;
mx[a].fi = mx[v.fi].fi + v.se;
}
else
{
mx[a].se = max(mx[a].se, mx[v.fi].fi + v.se);
}
}
out[a] = tim;
}
void dfs1(int a)
{
used[a] = 1;
for (int i = 0; i < adj[a].size(); i++)
{
pii v = adj[a][i];
if (used[v.fi]) continue;
dfs1(v.fi);
if (mx[a].fi == mx[v.fi].fi + v.se) make(in[v.fi], out[v.fi] + 1, mx[a].se - dist[a], 0, sz, 0);
else make(in[v.fi], out[v.fi] + 1, mx[a].fi - dist[a], 0, sz, 0);
}
}
void dfs2(int a, int w)
{
used[a] = 1;
ans[a] = max({dist[a], w, mx[a].fi});
for (int i = 0; i < adj[a].size(); i++)
{
pii v = adj[a][i];
if (used[v.fi]) continue;
if (mx[a].fi == mx[v.fi].fi + v.se)
{
dfs2(v.fi, max(w, mx[a].se) + v.se);
}
else
{
dfs2(v.fi, max(w, mx[a].fi) + v.se);
}
}
}
int LocateCentre(int N, int pp[], int S[], int D[]) {
n = N;
while (sz < n) sz <<= 1;
st.assign(sz << 1, 0);
for (int i = 0; i + 1 < n; i++)
{
int u = S[i];
int v = D[i];
adj[u].pb(mpr(v, pp[v]));
adj[v].pb(mpr(u, pp[u]));
}
dfs(0, 0);
for (int i = 0; i < n; i++) used[i] = 0;
dfs1(0);
for (int i = 0; i < n; i++) used[i] = 0;
dfs2(0, 0);
int mni = 0;
int mn = inf;
for (int i = 0; i < n; i++)
{
int x = max({ans[i] + pp[i], pp[i] + mx[i].fi - dist[i], dist[i] + get(in[i], 0, sz, 0)});
if (x < mn)
{
mni = i;
mn = x;
}
}
return mni;
}
Compilation message
traffic.cpp: In function 'void dfs(int, int)':
traffic.cpp:64:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
64 | for (int i = 0; i < adj[a].size(); i++)
| ~~^~~~~~~~~~~~~~~
traffic.cpp: In function 'void dfs1(int)':
traffic.cpp:87:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
87 | for (int i = 0; i < adj[a].size(); i++)
| ~~^~~~~~~~~~~~~~~
traffic.cpp: In function 'void dfs2(int, int)':
traffic.cpp:102:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
102 | for (int i = 0; i < adj[a].size(); i++)
| ~~^~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
7 ms |
37208 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
7 ms |
37208 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
7 ms |
37208 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
7 ms |
37208 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
