#include "towns.h"
#include <bits/stdc++.h>
using namespace std;
#define forn(i,n) for(int i=0;i<n;++i)
#define pb push_back
#define all(x) x.begin(), x.end()
#define pi pair<int,int>
#define f first
#define s second
const int inf=1e9+9;
const int _N=555;
int d[_N][_N];
int p1(int n) {
int mx=0;
int f,s;
forn(i,n) {
if (!i) continue;
int x=getDistance(0,i);
if (x>mx) {
mx=x;
f=i;
}
}
vector<int> a(n), b(n);
mx=0;
forn(i,n) {
if (i==f) continue;
int x=getDistance(f,i);
a[i]=x;
if (x>mx) {
mx=x;
s=i;
}
}
forn(i,n) {
if (i==s) continue;
int x=getDistance(s,i);
b[i]=x;
}
int ans=inf;
map<int,int> cnt;
set<int> s1,s2;
forn(i,n) {
if (i==f || i==s) continue;
int x=a[i], y=b[i], z=a[s];
int A=(x-y+z)/2;
int B=z-A;
int C=x-A;
ans=min(ans,max(A,B));
cnt[A]++;
s1.insert(A), s2.insert(B);
}
vector<int> x,y;
for(auto&t:s1) x.pb(t);
for(auto&t:s2) y.pb(t);
reverse(all(y));
int left=1;
forn(i,s1.size()) {
if (max(x[i],y[i])==ans) {
int a=left, b=cnt[x[i]];
int c=n-a-b;
if (max({a,b,c})<=n/2) return ans;
}
left+=cnt[x[i]];
}
return -ans;
}
struct DSU {
vector<int> p,sz;
DSU(int n) {forn(i,n)p.pb(i),sz.pb(1);}
int get(int u) {return p[u]==u?u:get(p[u]);}
void uni(int u, int v){
u=get(u),v=get(v); if (u==v)return; if (sz[u]<sz[v]) swap(u,v);
p[v]=u;sz[u]+=sz[v];
}
};
int p3(int n) {
forn(i,n) {
forn(j,i) {
int x=getDistance(i,j);
d[i][j]=d[j][i]=x;
}
}
int f=0,s=0;
forn(i,n) if (d[0][i]>d[0][f]) f=i;
forn(i,n) if (d[f][i]>d[f][s]) s=i;
int ans=inf;
map<int,int> cnt;
map<int,vector<int>> q;
vector<int> ok(n);
set<int> s1,s2;
forn(i,n) {
if (i==f || i==s) continue;
int x=d[f][i], y=d[s][i], z=d[f][s];
int A=(x-y+z)/2;
int B=z-A;
int C=x-A;
ans=min(ans,max(A,B));
ok[i]=C;
cnt[A]++;
q[A].pb(i);
s1.insert(A), s2.insert(B);
}
int left=1;
vector<int> x,y;
for(auto&t:s1)x.pb(t);
for(auto&t:s2)y.pb(t);
reverse(all(y));
forn(i,s1.size()) {
if (max(x[i],y[i])==ans) {
int right=n-left-cnt[x[i]];
int mx=max(left,right);
DSU dsu(n);
for(auto&u:q[x[i]]) {
for(auto&v:q[x[i]]) {
int dist = d[u][v];
if (dist < ok[u]+ok[v]) dsu.uni(u,v);
}
}
forn(j,n) mx=max(mx,dsu.sz[j]);
if (mx<=n/2) return ans;
}
left+=cnt[x[i]];
}
return -ans;
}
int p5(int n) {
vector<int> a(n), b(n), c(n);
int f=0;
forn(i,n) {
a[i]=getDistance(0,i);
if (a[i]>a[f]) f=i;
}
int s=0;
forn(i,n) {
b[i]=getDistance(f,i);
if (b[i]>b[s]) s=i;
}
forn(i,n) {
c[i]=getDistance(s,i);
}
set<int> st;
vector<int> d(n);
map<int,vector<int>> ok;
forn(i,n) {
if (i==f || i==s) continue;
int x=b[i], y=c[i], z=b[s];
int A=(x-y+z)/2;
d[i]=x-A;
st.insert(A);
ok[A].pb(i);
}
int ans=inf;
for(auto&x:st) {
int y=b[s]-x;
ans=min(ans,max(x,y));
}
int l=1;
for(auto&x:st) {
int y=b[s]-x;
if (max(x,y)!=ans) {
l+=ok[x].size();
continue;
}
int r=n-ok[x].size()-l;
if (max(l,r)>n/2) continue;
int t=ok[x].size();
if (max({l,r,t})<=n/2) return ans;
vector<int> a,b;
a = ok[x];
while (a.size()>1) {
int k = a.size();
if (k&1) b.pb(a[0]);
for (int i=k&1; i<a.size(); i+=2) {
int z = getDistance(a[i],a[i+1]);
int x = d[a[i]], y = d[a[i+1]];
if (z==x+y) continue;
b.pb(a[i]);
}
a=b;
b.clear();
}
if (!a.size()) return ans;
int u=a[0];
int sz=0;
for(auto&v:ok[x]) {
int z = getDistance(u,v);
int x = c[u], y = c[v];
if (z<x+y) ++sz;
}
if (sz<=n/2) return ans;
}
return -ans;
}
int hubDistance(int n, int sub) {
if (sub<=2 || sub==4) return p1(n);
if (sub==3) return p3(n);
if (sub==5) return p5(n);
return 0;
}
Compilation message
towns.cpp: In function 'int p1(int)':
towns.cpp:56:9: warning: unused variable 'C' [-Wunused-variable]
56 | int C=x-A;
| ^
towns.cpp:4:32: warning: comparison of integer expressions of different signedness: 'int' and 'std::set<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
4 | #define forn(i,n) for(int i=0;i<n;++i)
......
66 | forn(i,s1.size()) {
| ~~~~~~~~~~~
towns.cpp:66:3: note: in expansion of macro 'forn'
66 | forn(i,s1.size()) {
| ^~~~
towns.cpp:68:11: warning: declaration of 'a' shadows a previous local [-Wshadow]
68 | int a=left, b=cnt[x[i]];
| ^
towns.cpp:28:15: note: shadowed declaration is here
28 | vector<int> a(n), b(n);
| ^
towns.cpp:68:19: warning: declaration of 'b' shadows a previous local [-Wshadow]
68 | int a=left, b=cnt[x[i]];
| ^
towns.cpp:28:21: note: shadowed declaration is here
28 | vector<int> a(n), b(n);
| ^
towns.cpp: In function 'int p3(int)':
towns.cpp:4:32: warning: comparison of integer expressions of different signedness: 'int' and 'std::set<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
4 | #define forn(i,n) for(int i=0;i<n;++i)
......
124 | forn(i,s1.size()) {
| ~~~~~~~~~~~
towns.cpp:124:3: note: in expansion of macro 'forn'
124 | forn(i,s1.size()) {
| ^~~~
towns.cpp: In function 'int p5(int)':
towns.cpp:164:15: warning: declaration of 'd' shadows a global declaration [-Wshadow]
164 | vector<int> d(n);
| ^
towns.cpp:13:5: note: shadowed declaration is here
13 | int d[_N][_N];
| ^
towns.cpp:185:21: warning: conversion from 'std::vector<int>::size_type' {aka 'long unsigned int'} to 'int' may change value [-Wconversion]
185 | l+=ok[x].size();
| ^
towns.cpp:188:25: warning: conversion from 'std::vector<int>::size_type' {aka 'long unsigned int'} to 'int' may change value [-Wconversion]
188 | int r=n-ok[x].size()-l;
| ~~~~~~~~~~~~~~^~
towns.cpp:190:21: warning: conversion from 'std::vector<int>::size_type' {aka 'long unsigned int'} to 'int' may change value [-Wconversion]
190 | int t=ok[x].size();
| ~~~~~~~~~~^~
towns.cpp:193:17: warning: declaration of 'a' shadows a previous local [-Wshadow]
193 | vector<int> a,b;
| ^
towns.cpp:147:15: note: shadowed declaration is here
147 | vector<int> a(n), b(n), c(n);
| ^
towns.cpp:193:19: warning: declaration of 'b' shadows a previous local [-Wshadow]
193 | vector<int> a,b;
| ^
towns.cpp:147:21: note: shadowed declaration is here
147 | vector<int> a(n), b(n), c(n);
| ^
towns.cpp:196:21: warning: conversion from 'std::vector<int>::size_type' {aka 'long unsigned int'} to 'int' may change value [-Wconversion]
196 | int k = a.size();
| ~~~~~~^~
towns.cpp:198:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
198 | for (int i=k&1; i<a.size(); i+=2) {
| ~^~~~~~~~~
towns.cpp:200:13: warning: declaration of 'x' shadows a previous local [-Wshadow]
200 | int x = d[a[i]], y = d[a[i+1]];
| ^
towns.cpp:182:12: note: shadowed declaration is here
182 | for(auto&x:st) {
| ^
towns.cpp:200:26: warning: declaration of 'y' shadows a previous local [-Wshadow]
200 | int x = d[a[i]], y = d[a[i+1]];
| ^
towns.cpp:183:9: note: shadowed declaration is here
183 | int y=b[s]-x;
| ^
towns.cpp:212:11: warning: declaration of 'x' shadows a previous local [-Wshadow]
212 | int x = c[u], y = c[v];
| ^
towns.cpp:182:12: note: shadowed declaration is here
182 | for(auto&x:st) {
| ^
towns.cpp:212:21: warning: declaration of 'y' shadows a previous local [-Wshadow]
212 | int x = c[u], y = c[v];
| ^
towns.cpp:183:9: note: shadowed declaration is here
183 | int y=b[s]-x;
| ^
towns.cpp: In function 'int p1(int)':
towns.cpp:52:18: warning: 'second' may be used uninitialized in this function [-Wmaybe-uninitialized]
52 | if (i==f || i==s) continue;
| ^
towns.cpp:52:10: warning: 'first' may be used uninitialized in this function [-Wmaybe-uninitialized]
52 | if (i==f || i==s) continue;
| ^
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
10 ms |
360 KB |
Output is correct |
| 2 |
Correct |
8 ms |
340 KB |
Output is correct |
| 3 |
Correct |
1 ms |
212 KB |
Output is correct |
| 4 |
Correct |
12 ms |
356 KB |
Output is correct |
| 5 |
Correct |
12 ms |
364 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
10 ms |
360 KB |
Output is correct |
| 2 |
Correct |
9 ms |
340 KB |
Output is correct |
| 3 |
Correct |
12 ms |
352 KB |
Output is correct |
| 4 |
Correct |
12 ms |
356 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
10 ms |
596 KB |
Output is correct |
| 2 |
Correct |
13 ms |
572 KB |
Output is correct |
| 3 |
Correct |
0 ms |
340 KB |
Output is correct |
| 4 |
Correct |
13 ms |
572 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
11 ms |
352 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
8 ms |
340 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
8 ms |
340 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
