有n个人，每个人手里有一把手枪。一开始所有人都选定一个人瞄准（有可能瞄准自己）。然后他们按某个顺序开枪，且任意时刻只有一个人开枪。因此，对于不同的开枪顺序，最后死的人也不同。

输入n人数<1000000 每个人的aim

#include<bits/stdc++.h>

using namespace std;

typedef long long ll;

const int N=+;

int n;

struct node{

    int nxt,to;

}e[*N];

int hd[N],cnt=;

int du[N];//you xiang

int huan;//len of huan

bool on[N];//on the huan

bool vis[N];

bool die[N];

bool go[N];

bool has[N];

int to[N];

int mxans,mians;

void add(int x,int y){

    e[++cnt].nxt=hd[x];

    e[cnt].to=y;

    hd[x]=cnt;

}

bool fl;

int sta[N],top;

vector<int>mem;

int in[N];//in the sta

void dfs(int x,int in_edge){

//    cout<<" dfs "<<x<<" "<<endl;

    sta[++top]=x;

    vis[x]=;in[x]=;

    mem.push_back(x);

    for(int i=hd[x];i;i=e[i].nxt){

        int y=e[i].to;

        if(i==(in_edge^)) continue;

        if(vis[y]){

            if(in[y]&&!fl){

            //    cout<<" fin "<<y<<endl;

                fl=true;

                int z;//=sta[top];

                do{

                    z=sta[top];

                    on[z]=;in[z]=;

                    huan++;

                    top--;

                }while(z!=y);

            }

        }

        else dfs(y,i);

    }

    if(sta[top]==x) in[x]=,top--;

}

int q[N],l,r;

int len;//len of lian

void wrk(int x,int pre){//dfs on the huan

    go[x]=;

    //cout<<x<<" "<<pre<<endl;

    for(int i=hd[x];i;i=e[i].nxt){

        int y=e[i].to;

        if(y==pre) continue;

        if(go[y]) continue;

        if(on[y]){

            //cout<<" y "<<y<<endl;

            if(die[y]){

                mians+=len/;len=;

            }else len++;

            wrk(y,x);

        }

    }

}

void topo(){

    len=;

    l=,r=;

    //cout<<" huan "<<huan<<endl;

    //cout<<" mem "<<mem.size()<<endl;

    ///cout<<mians<<endl;

    for(int i=0;i<mem.size();i++){

        int id=mem[i];

        //cout<<id<<" "<<on[id]<<" "<<in[id]<<endl;

        if(du[id]==) q[++r]=id,has[id]=;

    }

    if(huan==||huan>) mxans+=mem.size()-max(r,);

    else mxans+=mem.size()-r;

    bool kil=false;

    int st;

    while(l<=r){

        int x=q[l++];

        //cout<<" x "<<x<<endl;

        //if(has[to[x]]) continue;

        if(!die[x]){

            if(!die[to[x]]) mians++,die[to[x]]=;

            if(on[to[x]])kil=,st=to[x];

        }

        du[to[x]]--;

        if(du[to[x]]==){

            q[++r]=to[x];

        }

    }

    if(kil){

        //cout<<" kil "<<st<<endl;

        //cout<<mians<<endl;

        wrk(st,);

        //cout<<" len "<<len<<endl;

        mians+=len/;

    }

    else{

        mians+=huan-(huan/);

    }

}

int main(){

    scanf("%d",&n);int y;

    for(int i=;i<=n;i++){

        scanf("%d",&y);to[i]=y;

        add(i,y);add(y,i);du[y]++;

    }

    for(int i=;i<=n;i++){

        if(!vis[i]){

            //cout<<" another "<<i<<endl;

            fl=false;

            huan=;

            mem.clear();

            dfs(i,);

            topo();

            //cout<<" mians "<<mians<<" mxans "<<mxans<<endl;

        }

    }

    cout<<mians<<" "<<mxans<<endl;

    return ;

}

/*

   Author: *Miracle*

   Date: 2018/10/14 19:28:35

*/