ex9_51.cpp

//! @Alan
//!
//! Exercise 9.51:
//! Write a class that has three unsigned members representing year,
//! month, and day. Write a constructor that takes a string representing
//! a date. Your constructor should handle a variety of date formats,
//! such as January 1, 1900, 1/1/1900, Jan 1, 1900, and so on.
//!

#include <iostream>
#include <string>
#include <vector>

class wy_Date {
public:
    wy_Date(const std::string& s);
    unsigned year;
    unsigned month;
    unsigned day;
};

int main()
{
    wy_Date d("99/21/3871");

    std::cout << d.day << " " << d.month << " " << d.year << " ";

    return 0;
}

wy_Date::wy_Date(const std::string& s)
{
    unsigned format = 0;

    //! 1/1/1900
    if (s.find_first_of("/") != std::string::npos) format = 0x10;

    //! Jan 1, 1900
    if (s.find_first_of(",") >= 4 && s.find_first_of(",") != std::string::npos)
        format = 0x01;

    switch (format) {

    //! format = 1/1/1900
    case 0x10:
        day = std::stoi(s.substr(0, s.find_first_of("/")));
        month = std::stoi(s.substr(s.find_first_of("/") + 1,
                                   s.find_last_of("/") - s.find_first_of("/")-1));
        year = std::stoi(s.substr(s.find_last_of("/") + 1, 4));
        break;

    //! format = January 1, 1900  or Jan 1, 1900
    case 0x01:
        day = std::stoi(
            s.substr(s.find_first_of("1234567890"),
                     s.find_first_of(",") - s.find_first_of("1234567890")));

        if (s.find("Jan") < s.size()) month = 1;
        if (s.find("Feb") < s.size()) month = 2;
        if (s.find("Mar") < s.size()) month = 3;
        if (s.find("Apr") < s.size()) month = 4;
        if (s.find("May") < s.size()) month = 5;
        if (s.find("Jun") < s.size()) month = 6;
        if (s.find("Jul") < s.size()) month = 7;
        if (s.find("Aug") < s.size()) month = 8;
        if (s.find("Sep") < s.size()) month = 9;
        if (s.find("Oct") < s.size()) month = 10;
        if (s.find("Nov") < s.size()) month = 11;
        if (s.find("Dec") < s.size()) month = 12;

        year = std::stoi(s.substr(s.find_last_of(" ") + 1, 4));
        break;
    }
}