标题

#include<bits/stdc++.h>
#define N 600011
using namespace std;
int hea[N],nex[N];
struct cmp
{
    bool operator() (const int &a,const int &b){
        return hea[a]<hea[b];
    }
};
priority_queue <int,vector<int>,cmp> q;
int main(void)
{
    int n,k,p;
    cin>>n>>k>>p;
    int a[p+1];
    for(int i=1;i<=p;i++) {
        scanf("%d",&a[i]);
    }
    for(int i=1;i<N;i++) hea[i]=p+1,nex[i]=p+1;
    for(int i=p;i>=1;i--){
        nex[i]=hea[a[i]],hea[a[i]]=i;
    /*    cout<<"nex["<<i<<"]="<<nex[i]<<endl;
        cout<<"hea["<<a[i]<<"]="<<hea[a[i]]<<endl;*/
    }
//    cout<<hea[3]<<" "<<nex[hea[3]]<<endl;
    int ans=0;
    int have[n+1];
    memset(have,0,sizeof have);
    int vis=1;
    int num=0;
/*    for(int i=1;i<=n;i++){
        cout<<i<<":";
        for(int j=hea[i];j;j=nex[j]){
            cout<<j<<" ";
            if(j>p) break;
        }
        cout<<endl;
    }*/
    for(int i=1;i<=p;i++){
        if(have[a[i]]==0){
        //    cout<<"have:"<<a[i]<<endl;
            ans++;
            vis++;
            if(vis>k+1){
                vis--;
                while(have[q.top()]==0) q.pop();
                have[q.top()]=0;
            //    cout<<"no:"<<q.top()<<endl;
                q.pop();
            }
        }
        have[a[i]]=1;
        hea[a[i]]=nex[hea[a[i]]];
        /*cout<<i<<":";
        for(int j=1;j<=n;j++) cout<<"hea["<<j<<"]="<<hea[j]<<endl;*/
        q.push(a[i]);
    }
    cout<<ans;
}
看题解思路和我几乎一样，为什么只有二十分/泪奔