1095. Cars on Campus (30)

看了几个别人写的，感觉这个还不错

http://blog.csdn.net/xyt8023y/article/details/48029443

写一次理解：

1.首先把这N条记录存储起来，按时间从小到大排序，时间统计转换为秒

2.遍历该N条记录，存放到map中，有in，有out，且inTime<outTime为一条完整的有效记录，把有效记录存起来；并同时计算该车的总停车时间（同一个车可能同时进出多次）

3.按时间从小到大的顺便排序2中存的有效记录，截止到查询时间，算出到此刻里面的车数

4.将2中的有效记录车存起来，从大到小排序他的总停车时间，有多个最大停车时间的车存起来，进行输出，最后输出最大的停车时间

CODE

#include <iostream>#include <stdio.h>#include <vector>#include <map>#include <algorithm>#include <string.h>using namespace std;struct Car{    string plate_num;    bool valid;     int inTime;    int outTime;    int total;    Car(){        valid = false;        inTime = outTime = -1;        total = 0;    }    bool operator < (const Car& other) const{        return total > other.total;    }};struct Record{    string plate_num;    int time;    char *state;    Record(string plate, int t, char *s){        plate_num = plate;        time = t;        state = s;    }    bool operator < (const Record& other) const {        return time < other.time;    }};struct QueryNode{    int time;    int value;    QueryNode(int t, int v){        time = t;        value = v;    }    bool operator < (const QueryNode& other) const{        return time < other.time;    }};int main(){#ifndef ONLINE_JUDGEfreopen("input.txt","r",stdin);#endif    int N,K;    scanf("%d %d",&N,&K);        vector<Record> records;int h,m,s;    for(int i = 0; i < N; i++){        string plate_num;        char *state = new char[2];        cin >> plate_num;        scanf("%d:%d:%d %s",&h,&m,&s,state);        records.push_back(Record(plate_num,h * 3600 + m * 60 + s,state));    }    sort(records.begin(),records.end());//把记录按时间顺序排序         map<string,Car> carMap;    vector<QueryNode> queryNodes;    for(int i = 0; i < records.size(); i++){        Record &r = records[i];//&表示引用，给record[i]起了一个名字叫r，不是一个新的变量，不分配存储空间         if(r.state[0] == 'i'){ // in            if(carMap.find(r.plate_num) == carMap.end()){//map中不存在该车                 Car c=Car();                c.plate_num = r.plate_num;                c.inTime = r.time;                carMap[r.plate_num] = c;            }else{                Car &c=carMap[r.plate_num];                c.inTime = r.time;//原来的inTime被覆盖             }        }else{ // out            if(carMap.find(r.plate_num) == carMap.end()){                Car c = Car();                c.plate_num = r.plate_num;                c.outTime = r.time;                carMap[r.plate_num] = c;            }else{                Car &c = carMap[r.plate_num];                c.outTime = r.time;                if(c.inTime != -1 && c.inTime < c.outTime){//是一条完整的有效记录                     QueryNode inQ = QueryNode(c.inTime,1);                    QueryNode outQ = QueryNode(c.outTime,-1);                    queryNodes.push_back(inQ);                    queryNodes.push_back(outQ);                    c.total += c.outTime - c.inTime;                    c.inTime = c.outTime = -1;//重置                     c.valid = true;                }            }        }    }    sort(queryNodes.begin(),queryNodes.end());       int cnt = 0;    int cur = 0;    for(int i = 0 ; i < K; i++){        scanf("%d:%d:%d",&h,&m,&s);        int t = h*3600+m*60+s;        while(cur<queryNodes.size()){            QueryNode q=queryNodes[cur];            if(q.time<=t){                cnt+= q.value;                cur++;            }else{                break;            }        }        printf("%d\n",cnt);    }vector<Car> validCars;    for(map<string,Car>::iterator it = carMap.begin(); it != carMap.end(); it++){        Car &c = it->second;        if(c.valid){            Car c = it->second;            validCars.push_back(c);        }    }    sort(validCars.begin(),validCars.end());        int maxTotal = validCars[0].total;    vector<string> carList;    carList.push_back(validCars[0].plate_num);    for(int i=1;i<validCars.size();i++){        Car c=validCars[i];        if(c.total==maxTotal){            carList.push_back(c.plate_num);        }else{            break;        }    }    sort(carList.begin(),carList.end());        for(int i = 0; i < carList.size(); i++){        printf("%s ",carList[i].c_str());    }    h = maxTotal / 3600;    m = (maxTotal - h * 3600) / 60;    s = maxTotal % 60;    printf("%02d:%02d:%02d\n",h,m,s);       #ifndef ONLINE_JUDGEfclose(stdin);#endif    return 0;}