#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<int,int>
#define OK puts("OK");
#define NO puts("NO");
#define YES puts("YES");
#define fr first
#define sc second
#define ret return
#define scanl(a) scanf("%lld",&a);
#define scanll(a,b) scanf("%lld %lld",&a, &b);
#define scanlll(a,b,c) scanf("%lld %lld %lld",&a,&b,&c);
#define scan1(a) scanf("%d",&a);
#define scan2(a,b) scanf("%d %d",&a, &b);
#define scan3(a,b,c) scanf("%d %d %d",&a,&b,&c);
#define all(s) s.begin(),s.end()
#define allr(s) s.rbegin(),s.rend()
#define pb push_back
#define sz(v) (int)v.size()
#define endi puts("");
#define eps 1e-12
const int N = 1e6+12,INF=1e9+7;
vector <int> g[N],cycle,v;
bool vis[N],bas[N];
int ans[N],pos,dis[N],coun;
void dfs(int x,int p){
vis[x] = 1;
int i,j;
v.pb(x);
for (i=0;i<g[x].size();++i){
int to = g[x][i];
if (vis[to] == 1 && to != p){
bool f=0;
for (j=0;j<v.size();++j){
if (v[j] == to)f=1;
if (f){
cycle.pb(v[j]);
}
}
}
if (vis[to] == 0){
dfs(to,x);
}
}
v.pop_back();
}
void dis_dfs(int x,int p,int cnt){
int i,mx = 0;
dis[pos] = max(dis[pos],cnt);
for (i=0;i<g[x].size();++i){
int to = g[x][i];
if (bas[to] || to == p)continue;
dis_dfs(to,x,cnt+1);
}
}
int maax;
void ans_dfs(int x,int p,int cnt){
int i = 0;
if (cnt == maax) coun++;
for (i=0;i<g[x].size();++i){
int to = g[x][i];
if (bas[to] || to == p)continue;
ans_dfs(to,x,cnt+1);
}
}
main(){
int n,m,i,j;
scan1(n)
for (i=1;i<=n;++i){
int x,y;
scan2(x,y)
g[x].pb(y);
g[y].pb(x);
}
dfs(1,0);
if (cycle.size() == n){
cout <<n;
ret 0;
}
for (i=0;i<cycle.size();++i){
bas[cycle[i]]=1;
}
for (i=0;i<cycle.size();++i){
pos=cycle[i];
dis_dfs(cycle[i],0,0);
maax = max(maax,dis[pos]);
}
for (i=0;i<cycle.size();++i){
ans_dfs(cycle[i],0,0);
}
cout <<coun*2;
}
Compilation message
shymbulak.cpp: In function 'void dfs(int, int)':
shymbulak.cpp:32:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
32 | for (i=0;i<g[x].size();++i){
| ~^~~~~~~~~~~~
shymbulak.cpp:36:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
36 | for (j=0;j<v.size();++j){
| ~^~~~~~~~~
shymbulak.cpp: In function 'void dis_dfs(int, int, int)':
shymbulak.cpp:54:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
54 | for (i=0;i<g[x].size();++i){
| ~^~~~~~~~~~~~
shymbulak.cpp:52:11: warning: unused variable 'mx' [-Wunused-variable]
52 | int i,mx = 0;
| ^~
shymbulak.cpp: In function 'void ans_dfs(int, int, int)':
shymbulak.cpp:64:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
64 | for (i=0;i<g[x].size();++i){
| ~^~~~~~~~~~~~
shymbulak.cpp: At global scope:
shymbulak.cpp:71:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
71 | main(){
| ^
shymbulak.cpp: In function 'int main()':
shymbulak.cpp:81:22: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
81 | if (cycle.size() == n){
| ~~~~~~~~~~~~~^~~~
shymbulak.cpp:85:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
85 | for (i=0;i<cycle.size();++i){
| ~^~~~~~~~~~~~~
shymbulak.cpp:88:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
88 | for (i=0;i<cycle.size();++i){
| ~^~~~~~~~~~~~~
shymbulak.cpp:93:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
93 | for (i=0;i<cycle.size();++i){
| ~^~~~~~~~~~~~~
shymbulak.cpp:72:11: warning: unused variable 'm' [-Wunused-variable]
72 | int n,m,i,j;
| ^
shymbulak.cpp:72:15: warning: unused variable 'j' [-Wunused-variable]
72 | int n,m,i,j;
| ^
shymbulak.cpp:14:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
14 | #define scan1(a) scanf("%d",&a);
| ~~~~~^~~~~~~~~
shymbulak.cpp:73:5: note: in expansion of macro 'scan1'
73 | scan1(n)
| ^~~~~
shymbulak.cpp:15:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
15 | #define scan2(a,b) scanf("%d %d",&a, &b);
| ~~~~~^~~~~~~~~~~~~~~~
shymbulak.cpp:76:9: note: in expansion of macro 'scan2'
76 | scan2(x,y)
| ^~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
16 ms |
23788 KB |
Output is correct |
| 2 |
Incorrect |
16 ms |
23788 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
17 ms |
23916 KB |
Output is correct |
| 2 |
Incorrect |
18 ms |
23916 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
86 ms |
26988 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
