Submission #377227

#	Time	Username	Problem	Language	Result	Execution time	Memory
377227		rrrr10000	Duathlon (APIO18_duathlon)	C++14	0 / 100	1087 ms	38172 KiB

count_triplets

#include <bits/stdc++.h>
using namespace std;
#define rep(i, n)  for(long long i=0;i<(long long)(n);i++)
#define REP(i,k,n) for(long long i=k;i<(long long)(n);i++)
#define pb emplace_back
#define lb(v,k) (lower_bound(all(v),(k))-v.begin())
#define ub(v,k) (upper_bound(all(v),(k))-v.begin())
#define fi first
#define se second
#define pi M_PI
#define PQ(T) priority_queue<T>
#define SPQ(T) priority_queue<T,vector<T>,greater<T>>
#define dame(a) {out(a);return 0;}
#define decimal cout<<fixed<<setprecision(15);
#define all(a) a.begin(),a.end()
#define rsort(a) {sort(all(a));reverse(all(a));}
#define dupli(a) {sort(all(a));a.erase(unique(all(a)),a.end());}
typedef long long ll;
typedef pair<ll,ll> P;
typedef tuple<ll,ll,ll> PP;
typedef tuple<ll,ll,ll,ll> PPP;
using vi=vector<ll>;
using vvi=vector<vi>;
using vvvi=vector<vvi>;
using vvvvi=vector<vvvi>;
using vp=vector<P>;
using vvp=vector<vp>;
using vb=vector<bool>;
using vvb=vector<vb>;
const ll inf=1001001001001001001;
const ll INF=1001001001;
const ll mod=1000000007;
const double eps=1e-10;
template<class T> bool chmin(T&a,T b){if(a>b){a=b;return true;}return false;}
template<class T> bool chmax(T&a,T b){if(a<b){a=b;return true;}return false;}
template<class T> void out(T a){cout<<a<<'\n';}
template<class T> void outp(T a){cout<<'('<<a.fi<<','<<a.se<<')'<<'\n';}
template<class T> void outvp(T v){rep(i,v.size())cout<<'('<<v[i].fi<<','<<v[i].se<<')';cout<<'\n';}
template<class T> void outvvp(T v){rep(i,v.size())outvp(v[i]);}
template<class T> void outv(T v){rep(i,v.size()){if(i)cout<<' ';cout<<v[i];}cout<<'\n';}
template<class T> void outvv(T v){rep(i,v.size())outv(v[i]);}
template<class T> bool isin(T x,T l,T r){return (l)<=(x)&&(x)<=(r);}
template<class T> void yesno(T b){if(b)out("yes");else out("no");}
template<class T> void YesNo(T b){if(b)out("Yes");else out("No");}
template<class T> void YESNO(T b){if(b)out("YES");else out("NO");}
template<class T> void outset(T s){auto itr=s.begin();while(itr!=s.end()){if(itr!=s.begin())cout<<' ';cout<<*itr;itr++;}cout<<'\n';}
void outs(ll a,ll b){if(a>=inf-100)out(b);else out(a);}
ll gcd(ll a,ll b){if(b==0)return a;return gcd(b,a%b);}
ll modpow(ll a,ll b){ll res=1;a%=mod;while(b){if(b&1)res=res*a%mod;a=a*a%mod;b>>=1;}return res;}
 

int main(){
    ll n,m;cin>>n>>m;
    vvp g(n);
    rep(i,m){
        ll a,b;cin>>a>>b;a--;b--;
        g[a].pb(b,i);g[b].pb(a,i);
    }
    vi root,lk(n),dep(n,-1),gr_ver(n,-1),gr_edge(m,-1);
    vb is_kansetsu(n,false);
    function<ll(ll,ll,ll)> dfs0=[&](ll i,ll p,ll d){
        dep[i]=d;lk[i]=d;
        for(auto x:g[i])if(x.fi!=p){
            if(dep[x.fi]!=-1)chmin(lk[i],dep[x.fi]);
            else chmin(lk[i],dfs0(x.fi,i,d+1));
        }
        return lk[i];
    };rep(i,n)if(dep[i]==-1){dfs0(i,-1,0);root.pb(i);}
    ll cmp=0;
    function<void(ll,ll,ll)> dfs=[&](ll i,ll p,ll e){
        for(auto x:g[i])if(x.fi!=p){
            if(dep[x.fi]==dep[i]+1){
                if(lk[x.fi]>=dep[i])gr_edge[x.se]=cmp++;
                else gr_edge[x.se]=gr_edge[e];
                dfs(x.fi,i,x.se);
            }
            else if(dep[x.fi]<dep[i])gr_edge[x.se]=gr_edge[e];
        }
    };for(ll x:root)dfs(x,-1,-1);
    rep(i,n){
        vi al;
        for(auto x:g[i])al.pb(gr_edge[x.se]);
        dupli(al);
        if(al.size()==0)gr_ver[i]=cmp++;
        else if(al.size()==1)gr_ver[i]=al[0];
        else{
            gr_ver[i]=cmp++;
            is_kansetsu[i]=true;
        }
    }
    vvi tree(cmp);
    rep(i,n)for(auto x:g[i])if(gr_edge[x.se]!=gr_ver[i]){
        tree[gr_edge[x.se]].pb(gr_ver[i]);
        tree[gr_ver[i]].pb(gr_edge[x.se]);
    }
    // outv(gr_ver);outv(gr_edge);
    // outvv(tree);
    vi sz(cmp);
    rep(i,n)sz[gr_ver[i]]++;
    vi ch(cmp,-1);
    ll ans=n*(n-1)*(n-2);
    ll tmp;
    function<void(ll,ll)> slv=[&](ll i,ll p){
        ch[i]=sz[i];
        for(ll x:tree[i])if(x!=p){
            slv(x,i);
            ch[i]+=ch[x];
            ans-=sz[i]*ch[x]*(ch[x]-1);
        }
    };
    function<void(ll,ll)> slv2=[&](ll i,ll p){
        for(ll x:tree[i])if(x!=p){
            slv2(x,i);
        }
        ans-=sz[i]*(tmp-ch[i])*(tmp-ch[i]-1);
    };
    rep(i,n)if(ch[i]==-1){
        slv(i,-1);
        tmp=ch[i];
        slv2(i,-1);
    }
    out(ans);
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 11
• Subtask 3: 0 / 8
• Subtask 4: 0 / 10
• Subtask 5: 0 / 13
• Subtask 6: 0 / 15
• Subtask 7: 0 / 20
• Subtask 8: 0 / 8
• Subtask 9: 0 / 10