《C++ Primer 第五版》练习9.51参考答案

标签：c++   c++ primer   习题答案   

//Date.h

#include <map>
#include <string>
#include <vector>
using namespace std;
struct Date
{

        explicit Date(const string & info){//检测输入格式，尝试初始化，若失败则进行errorInit
            if(mymap.empty()){
              initMap();
            }
            if(!checkInfoFormat(info)){
               errorInit();
               return;
            }
            string monthStr=info.substr(0,info.find_first_of(", /"));
            string dayStr=info.substr(info.find_first_of(", /")+1,info.find_last_of(", /")-info.find_first_of(", /")-1);
            string yearStr=info.substr(info.find_last_of(", /")+1,info.size());
            if(!tryToInit({yearStr,monthStr,dayStr})){
                errorInit();
            }


             cout<<"year: "<<year<<endl;
             cout<<"month: "<<month<<endl;
             cout<<"day: "<<day<<endl;

        }

        unsigned year;
        unsigned month;
        unsigned day;
        static void initMap();

        private:
           bool checkDate(){//检查日期是否合法

            if(year>10000||month>12||day>31)
             return false;

             if(month==4||month==6||month==9||month==11){
               if(day>30)
               return false;
             }
             if(month==2){

              if(checkYear(year)&&day>29){

              return false;
              }
              if(!checkYear(year)&&day>28)
              return false;

             }
             return true;
           }
           bool checkYear(unsigned year)//检测闰年
           {

return (((year % 4 == 0) && (year % 100 != 0)) || (year % 400 == 0)) ? true : false;

           }
           static map<string,unsigned> mymap;
           void errorInit()
           {
                year=1970;
                month=1;
                day=1;
           }
          
           bool tryToInit(const vector<string> & data)//尝试初始化
           {
               try{
                 year=stoul(data[0]);
                 day=stoul(data[2]);
               }catch(invalid_argument & error){
                 return false;
               }

               try{
                 month=stoul(data[1]);
               }catch(invalid_argument & error){

                  if(mymap.find(data[1])==mymap.end())
                  return false;
                  month=mymap[data[1]];
               }

               return checkDate();

           }
           bool checkInfoFormat(const string & info)//检测格式是否正确
           {
              if(info.empty())
               return false;
              if(info.find_first_of(", /")==info.size())
               return false;
              if(info.find_first_of(", /")==info.find_last_of(", /"))
               return false;

               return true;
           }



};

//Date.cpp
map<string,unsigned> Date::mymap;
void Date::initMap(){
                  mymap.insert(make_pair<string,unsigned>("January",1));
                  mymap.insert(make_pair<string,unsigned>("Jan",1));
                  mymap.insert(make_pair<string,unsigned>("February",2));
                  mymap.insert(make_pair<string,unsigned>("Feb",2));
                  mymap.insert(make_pair<string,unsigned>("March",3));
                  mymap.insert(make_pair<string,unsigned>("Mar",3));
                  mymap.insert(make_pair<string,unsigned>("April",4));
                  mymap.insert(make_pair<string,unsigned>("Apr",4));
                  mymap.insert(make_pair<string,unsigned>("May",5));
                  mymap.insert(make_pair<string,unsigned>("June",6));
                  mymap.insert(make_pair<string,unsigned>("Jun",6));
                  mymap.insert(make_pair<string,unsigned>("July",7));
                  mymap.insert(make_pair<string,unsigned>("Jul",7));
                  mymap.insert(make_pair<string,unsigned>("August",8));
                  mymap.insert(make_pair<string,unsigned>("Aug",8));
                  mymap.insert(make_pair<string,unsigned>("September",9));
                  mymap.insert(make_pair<string,unsigned>("Sep",9));
                  mymap.insert(make_pair<string,unsigned>("October",10));
                  mymap.insert(make_pair<string,unsigned>("Oct",10));
                  mymap.insert(make_pair<string,unsigned>("November",11));
                  mymap.insert(make_pair<string,unsigned>("Nov",11));
                  mymap.insert(make_pair<string,unsigned>("December",12));
                  mymap.insert(make_pair<string,unsigned>("Dec",12));
            }
//表驱动法的应用

《C++ Primer 第五版》练习9.51参考答案,布布扣,bubuko.com

《C++ Primer 第五版》练习9.51参考答案

标签：c++   c++ primer   习题答案   

原文地址：http://blog.csdn.net/zjq2008wd/article/details/38537923