#include<bits/stdc++.h>
#define pb push_back
#define fi first
#define se second
#define mp make_pair
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef long double ld;
template <typename T> bool chkmin(T &x,T y){return x>y?x=y,1:0;}
template <typename T> bool chkmax(T &x,T y){return x<y?x=y,1:0;}
ll readint(){
ll x=0,f=1; char ch=getchar();
while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();}
return x*f;
}
int n,tot;
int v[1000005],nxt[1000005],h[500005],mx[500005],cnt[500005];
ll res=0,c=1;
multiset<int> st;
map<int,int> m;
vector<pii> f;
void addedge(int x,int y){
v[++tot]=y; nxt[tot]=h[x]; h[x]=tot;
v[++tot]=x; nxt[tot]=h[y]; h[y]=tot;
}
void dfs(int x,int px,int d){
mx[x]=d;
cnt[x]=1;
for(int p=h[x];p;p=nxt[p]){
if(v[p]==px) continue;
dfs(v[p],x,d+1);
if(mx[v[p]]==mx[x]) cnt[x]+=cnt[v[p]];
else if(mx[x]<mx[v[p]]) cnt[x]=cnt[v[p]];
mx[x]=max(mx[x],mx[v[p]]);
}
}
void reroot(int x,int px,int d){
f.clear();
for(int p=h[x];p;p=nxt[p]){
if(v[p]!=px) mx[v[p]]-=d;
f.pb(mp(mx[v[p]],cnt[v[p]]));
}
sort(f.rbegin(),f.rend());
if((int)f.size()>=3){
ll cur=0,cc=0;
cur=f[0].fi*1ll*(f[1].fi+f[2].fi);
ll s=0;
for(int j=0;j<f.size();j++){
if(f[j].fi==f[2].fi) cc+=s*f[j].se;
if(f[j].fi==f[1].fi) s+=f[j].se;
}
if(res<cur) res=cur,c=cc;
else if(res==cur) c+=cc;
}
int mx_bef=mx[x],cnt_bef=cnt[x];
st.clear(); m.clear();
for(int p=h[x];p;p=nxt[p]){
st.insert(mx[v[p]]);
m[mx[v[p]]]+=cnt[v[p]];
}
st.insert(0);
m[0]+=1;
for(int p=h[x];p;p=nxt[p]){
if(v[p]==px) continue;
st.erase(st.find(mx[v[p]]));
m[mx[v[p]]]-=cnt[v[p]];
mx[x]=*prev(st.end())+1;
cnt[x]=m[mx[x]-1];
reroot(v[p],x,d+1);
st.emplace(mx[v[p]]);
m[mx[v[p]]]+=cnt[v[p]];
}
mx[x]=mx_bef;
cnt[x]=cnt_bef;
}
int main(){
n=readint();
for(int i=1;i<n;i++) addedge(readint(),readint());
dfs(1,1,0);
reroot(1,1,0);
printf("%lld %lld\n",res,c);
return 0;
}
Compilation message
road.cpp: In function 'void reroot(int, int, int)':
road.cpp:61:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
61 | for(int j=0;j<f.size();j++){
| ~^~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
6500 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
6500 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
6500 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
