CCF2019-12-2回收站选址

记录一下

#include <iostream>
#include <vector>
#include <utility>
#include <string.h>
#include <algorithm>
using namespace std;

vector<pair<int,int>> point;
bool isStation(vector<pair<int,int>>::iterator it){
    vector<pair<int,int>> pv;
    pv.push_back(make_pair((*it).first-1,(*it).second));
    pv.push_back(make_pair((*it).first+1,(*it).second));
    pv.push_back(make_pair((*it).first,(*it).second-1));
    pv.push_back(make_pair((*it).first,(*it).second+1));
    for(pair<int,int> a:pv)
        if(find(point.begin(),point.end(),a)==point.end())
            return false;
    return true;

}
int grade(vector<pair<int,int>>::iterator it){
    vector<pair<int,int>> pv;
    pv.push_back(make_pair((*it).first-1,(*it).second-1));
    pv.push_back(make_pair((*it).first-1,(*it).second+1));
    pv.push_back(make_pair((*it).first+1,(*it).second-1));
    pv.push_back(make_pair((*it).first+1,(*it).second+1));
    int sum=0;
    for(pair<int,int> a:pv)
        if(find(point.begin(),point.end(),a)!=point.end())
        sum++;
    return sum;
}
int main()
{
    int n;
    cin>>n;
    for(int i=0;i<n;i++){
        int x,y;
        cin>>x>>y;
        pair<int,int> a(x,y);
        point.push_back(a);
    }
    int sum[5];
    memset(sum,0,sizeof(sum));
    for(vector<pair<int,int>>::iterator it=point.begin();it!=point.end();it++)
        if(isStation(it)) sum[grade(it)]++;
    for(int i=0;i<5;i++){
        cout<<sum[i];
        if(i!=4) cout<<endl;
    }
    return 0;
}