#include<bits/stdc++.h>
using namespace std;
#define int int64_t
#define pb push_back
#define pii pair<int, int>
#define st first
#define nd second
#define sz(x) (int)(x).size()
#define all(x) (x).begin(), (x).end()
ostream& operator<<(ostream &os, pair<auto, auto> x) {
os << "{" << x.st << ", " << x.nd << "}";
return os;
}
const int MAXN = 100'009;
pii tab[MAXN];
int dis[MAXN];
int dir[MAXN];
vector<int> G[MAXN][4];
int n;
namespace B1 {
int f(int a, int b) {
return abs(tab[a].st-tab[b].st)+abs(tab[a].nd-tab[b].nd);
}
int dijkstra(int x, int x_dir) {
fill(dis, dis+n, 1e9);
int cnt = 0;
dis[x] = 0;
dir[x] = x_dir;
priority_queue<pii, vector<pii>, greater<pii>> Q;
Q.push({dis[x], x});
while(sz(Q)) {
auto [d_x, x] = Q.top();
Q.pop();
if(d_x!=dis[x]) continue;
cnt++;
// cerr << "dij: " << tab[x] << " " << d_x << "\n";
for(int y:G[x][dir[x]]) {
// cerr << "one: " << tab[y] << "\n";
int d = f(x, y);
if(d<d_x) continue;
if(d<dis[y]) {
dis[y] = d;
dir[y] = (dir[x]+1)%4;
Q.push({dis[y], y});
}
}
for(int y:G[x][(dir[x]+1)%4]) {
// cerr << "two: " << tab[y] << "\n";
int d = f(x, y);
if(d<d_x) continue;
if(d<dis[y]) {
dis[y] = d;
int ndir = dir[x]-1;
if(ndir<0) ndir+=4;
dir[y] = ndir;
Q.push({dis[y], y});
}
}
}
return cnt;
}
}
namespace B2 {
int f(int a, int b) {
return tab[a].st-tab[b].st+tab[a].nd-tab[b].nd;
}
int dijkstra(int x, int x_dir) {
fill(dis, dis+n, 1e9);
int cnt = 0;
dis[x] = 0;
dir[x] = x_dir;
priority_queue<pii, vector<pii>, greater<pii>> Q;
Q.push({dis[x], x});
while(sz(Q)) {
auto [d_x, x] = Q.top();
Q.pop();
if(d_x!=dis[x]) continue;
cnt++;
for(int y:G[x][dir[x]]) {
int d = f(x, y);
if(d<d_x) continue;
if(d<dis[y]) {
dis[y] = d;
dir[y] = (dir[x]+1)%4;
Q.push({dis[y], y});
}
}
for(int y:G[x][(dir[x]+1)%4]) {
int d = f(x, y);
if(d<d_x) continue;
if(d<dis[y]) {
dis[y] = d;
int ndir = dir[x]-1;
if(ndir<0) ndir+=4;
dir[y] = ndir;
Q.push({dis[y], y});
}
}
}
return cnt;
}
}
int32_t main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cin >> n;
for(int i=0;i<n;i++) {
int a, b;
cin >> a >> b;
tab[i] = {a+b, a-b};
// cerr << i << ": " << tab[i] << "\n";
}
for(int i=0;i<n;i++) {
auto [a1, b1] = tab[i];
// if(i==0) cerr << "TU: " << tab[i] << "\n";
for(int j=0;j<n;j++) {
auto [a2, b2] = tab[j];
if(a1<a2&&b1==b2) {
// if(i==0) cerr << "0: " << tab[j] << "\n";
G[i][0].pb(j);
}
if(a1==a2&&b2>b1) {
// if(i==0) cerr << "1: " << tab[j] << "\n";
G[i][1].pb(j);
}
if(a1>a2&&b1==b2) {
// if(i==0) cerr << "2: " << tab[j] << "\n";
G[i][2].pb(j);
}
if(a1==a2&&b2<b1) {
// if(i==0) cerr << "3: " << tab[j] << "\n";
G[i][3].pb(j);
}
}
}
int ans1 = 0;
// ans = dijkstra(0, 0);
for(int i=0;i<4;i++) {
ans1 = max(ans1, B1::dijkstra(0, i));
}
int ans2 = 0;
// ans = dijkstra(0, 0);
for(int i=0;i<4;i++) {
ans2 = max(ans2, B2::dijkstra(0, i));
}
// assert(ans1>=ans2);
cout << ans2 << "\n";
}
Compilation message
fever.cpp:12:39: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
12 | ostream& operator<<(ostream &os, pair<auto, auto> x) {
| ^~~~
fever.cpp:12:45: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
12 | ostream& operator<<(ostream &os, pair<auto, auto> x) {
| ^~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
13044 KB |
Output is correct |
2 |
Correct |
2 ms |
12892 KB |
Output is correct |
3 |
Incorrect |
2 ms |
12892 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
13044 KB |
Output is correct |
2 |
Correct |
2 ms |
12892 KB |
Output is correct |
3 |
Incorrect |
2 ms |
12892 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
3 ms |
12888 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
13044 KB |
Output is correct |
2 |
Correct |
2 ms |
12892 KB |
Output is correct |
3 |
Incorrect |
2 ms |
12892 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
13044 KB |
Output is correct |
2 |
Correct |
2 ms |
12892 KB |
Output is correct |
3 |
Incorrect |
2 ms |
12892 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
13044 KB |
Output is correct |
2 |
Correct |
2 ms |
12892 KB |
Output is correct |
3 |
Incorrect |
2 ms |
12892 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
13044 KB |
Output is correct |
2 |
Correct |
2 ms |
12892 KB |
Output is correct |
3 |
Incorrect |
2 ms |
12892 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |