USTC 1281 Unhappy dots STL map

这题被set坑了,问了问戴牛原来multiset的count 复杂度很大,是logn+o(元素个数),所以我悲剧的一直TLE啊(除夕夜就这么悲剧....)

其实是用map

#include<stdio.h>
#include<utility>
#include<map>
#include<string.h>
using namespace std;
int x[100005],y[100005];
int visit[100005];
int h[5]={1,-1,0,0,0};
int g[5]={0,0,1,-1,0};
int main(){
    int k,n,m,i,j,u,v;
    int ca=0;
    while(scanf("%d %d %d",&k,&n,&m) && !(k==0 && n==0 && m==0)){
		memset(visit,0,sizeof(visit));
        map<pair<int,int>,int>st;
		for(i=1;i<=k;i++){
			scanf("%d %d",&x[i],&y[i]);
			map<pair<int,int>, int>::iterator it;
			it=st.find(make_pair(x[i],y[i]));
			if(it==st.end())
				st.insert(make_pair(make_pair(x[i],y[i]),1));
			else
				it->second++;
		}
		int sum=0;
		for(i=1;i<=k;i++){
			int tem=0,temp;
			for(int j=0;j<=4;j++){
				int p=x[i]+h[j];
				int q=y[i]+g[j];
				if(p>m || p<1 || q>n ||q<1)
					continue;
				map<pair<int,int>, int>::iterator it;
				it=st.find(make_pair(p,q));
				if(it==st.end())
					continue;
				if(j!=4)
					tem+=it->second;
				else
					tem+=it->second-1;
				if(tem>=2)
					break;
			}
        if(tem<2)
            sum++;
    }
    printf("Case %d: %d\n",++ca,sum);
    }
    return 0;
}

顺便也把我TLE的set贴一下

#include<stdio.h>
#include<utility>
#include<set>
using namespace std;
int x[100005],y[100005];
int h[5]={1,-1,0,0,0};
int g[5]={0,0,1,-1,0};
int main(){
    int k,n,m,i,j,u,v;
    int ca=0;
    while(scanf("%d %d %d",&k,&n,&m) && !(k==0 && n==0 && m==0)){
        multiset<pair<int,int> >st;
    for(i=1;i<=k;i++){
        scanf("%d %d",&x[i],&y[i]);
        st.insert(make_pair(x[i],y[i]));
    }
    int sum=0;
    for(i=1;i<=k;i++){
        int tem=0;
        for(int j=0;j<=4;j++){
            int p=x[i]+h[j];
            int q=y[i]+g[j];
            if(p>m || p<1 || q>n ||q<1)
                continue;
            if(j!=4)
                tem+=st.count(make_pair(p,q));
            else
                tem+=st.count(make_pair(p,q))-1;
            if(tem>=2)
                break;
        }
        if(tem<2)
            sum++;
    }
    printf("Case %d: %d\n",++ca,sum);
    }
    return 0;
}

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