Submission #341399

#	Time	Username	Problem	Language	Result	Execution time	Memory
341399		beksultan04	Shymbulak (IZhO14_shymbulak)	C++14	0 / 100	167 ms	52972 KiB

shymbulak

#include <bits/stdc++.h>
using namespace std;
#define int 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 = 2e6+12,INF=1e9+7;

vector <int> g[N],cycle,v;
pii ver[N];
bool bosh[N],vis[N];
void dfs_cycle(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_cycle(to,x);
        }
    }
    v.pop_back();
}

int dlina[N],colichestvo[N];

int ans,cont;
void dfs_diametr(int x,int p){
    int i;
    vector <pii> tmp;
    for (i=0;i<g[x].size();++i){
        if (g[x][i] == p || bosh[g[x][i]])continue;
        dfs_diametr(g[x][i],x);
        tmp.pb({dlina[g[x][i]],colichestvo[g[x][i]]});
    }
    if (tmp.size() == 0){
        colichestvo[x] = 1;
        ret;
    }
    sort(allr(tmp));
    int mx = tmp[0].fr,cnt = tmp[0].sc;
    for (i=1;i<tmp.size();++i){
        if (tmp[i].fr == mx){
            cnt += tmp[i].sc;
        }

    }
    dlina[x] = mx+1;
    colichestvo[x] = cnt;
}

void calc(int x,int y,int m){
    int dist = min(abs(x-y),m-abs(x-y));
    dist += dlina[cycle[x]];
    dist += dlina[cycle[y]];
    if (ans < dist){
        ans = dist;
        cont=0;
    }
    if (dist == ans){
        if (abs(x-y) == (m-abs(x-y))){
            cont += max(colichestvo[cycle[x]],1ll)*max(1ll,colichestvo[cycle[y]])*2ll;
        }
        else
            cont += colichestvo[cycle[x]]*colichestvo[cycle[y]]*1ll;
    }
}

void posledniy_dfs(int x,int p){
    vector <pii> tmp;
    int i;
    for (i=0;i<g[x].size();++i){
        if (g[x][i] == p || bosh[g[x][i]])continue;
        posledniy_dfs(g[x][i],x);
        tmp.pb({dlina[g[x][i]],colichestvo[g[x][i]]});
    }
    sort(allr(tmp));
    if (tmp.empty())ret;
    vector <int> xixi;
    int mx = tmp[0].fr+1,cnt=tmp[0].sc,f=0;
    xixi.pb(cnt);
    int sum=0,bla=0;
    for (i=1;i<tmp.size();++i){
        if (tmp[i].fr+1+mx > ans){
            ans = tmp[i].fr+1+mx;
            f=2;
        }
        if (ans == tmp[i].fr+1+mx){
            xixi.pb(tmp[i].sc);
            f = max(f,1ll);
        }
        else break;
    }
    for (i=0;i<xixi.size();++i){
        sum+=xixi[i];
        bla += xixi[i]*xixi[i];
    }
    sum *= sum;
    sum-=bla;
    sum/=2;
    if (f==2)cont=sum;
    else if (f==1){
        cont+=sum;
    }
}

main(){

    int n,i,j;
    cin>>n;
    for (i=1;i<=n;++i){
        int x,y;
        cin>>x>>y;
        g[x].pb(y);
        g[y].pb(x);
    }
    dfs_cycle(1,0);
    int m = cycle.size();
    for (i=0;i<m;++i)
        bosh[cycle[i]] = 1;
    for (i=0;i<m;++i){
        dfs_diametr(cycle[i],0);
//        cout <<cycle[i]<<"-"<<dlina[cycle[i]]<<" ";
//        cout <<colichestvo[cycle[i]]<<"\n";
    }
    for (i=0;i<m;++i){
        for (j=i+1;j<m;++j){
            calc(i,j,m);
        }
    }
    for (i=0;i<m;++i){
        posledniy_dfs(cycle[i],0);
    }
    cout <<cont;

}
/*
16
1 2
2 3
3 4
4 5
5 6
6 7
7 8
8 9
6 10
10 11
10 12
5 13
2 14
2 15
15 16
7 1
*/

Compilation message (stderr)

shymbulak.cpp: In function 'void dfs_cycle(long long int, long long int)':
shymbulak.cpp:32:15: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long 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: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |             for (j=0;j<v.size();++j){
      |                      ~^~~~~~~~~
shymbulak.cpp: In function 'void dfs_diametr(long long int, long long int)':
shymbulak.cpp:57:15: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   57 |     for (i=0;i<g[x].size();++i){
      |              ~^~~~~~~~~~~~
shymbulak.cpp:68:15: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   68 |     for (i=1;i<tmp.size();++i){
      |              ~^~~~~~~~~~~
shymbulak.cpp: In function 'void posledniy_dfs(long long int, long long int)':
shymbulak.cpp:98:15: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   98 |     for (i=0;i<g[x].size();++i){
      |              ~^~~~~~~~~~~~
shymbulak.cpp:109:15: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  109 |     for (i=1;i<tmp.size();++i){
      |              ~^~~~~~~~~~~
shymbulak.cpp:120:15: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  120 |     for (i=0;i<xixi.size();++i){
      |              ~^~~~~~~~~~~~
shymbulak.cpp: At global scope:
shymbulak.cpp:133:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  133 | main(){
      |      ^

• Subtask 1: 0 / 30
• Subtask 2: 0 / 20
• Subtask 3: 0 / 50