编程练习答案——第14章

  1 // chapter14_1_wine.h
  2 
  3 #ifndef LEARN_CPP_CHAPTER14_1_WINE_H
  4 #define LEARN_CPP_CHAPTER14_1_WINE_H
  5 
  6 #include <valarray>
  7 #include <string>
  8 
  9 typedef std::valarray<int> ArrayInt;
 10 typedef std::pair<ArrayInt, ArrayInt> PairArray;
 11 
 12 class Wine {
 13 private:
 14     std::string label;
 15     int numofyears;
 16     PairArray year_bots;
 17 public:
 18     Wine();
 19     Wine(const char * l, int y, const int ye[], const int bot[]);
 20     Wine(const char * l, int y);
 21     ~Wine();
 22     void GetBottles();
 23     std::string & Label();
 24     int sum() const;
 25     void show() const;
 26 };
 27 
 28 #endif //LEARN_CPP_CHAPTER14_1_WINE_H
 29 
 30 
 31 // chapter14_1_wine.cpp
 32 
 33 #include "chapter14_1_wine.h"
 34 #include <iostream>
 35 
 36 Wine::Wine() {
 37     label = "none";
 38     numofyears = 0;
 39     year_bots.first = ArrayInt(numofyears);
 40     year_bots.second = ArrayInt(numofyears);
 41 }
 42 
 43 Wine::Wine(const char *l, int y, const int *ye, const int *bot) {
 44     label = l;
 45     numofyears = y;
 46     year_bots.first = ArrayInt(numofyears);
 47     year_bots.second = ArrayInt(numofyears);
 48     for (int i = 0; i < numofyears; ++ i) {
 49         year_bots.first[i] = ye[i];
 50         year_bots.second[i] = bot[i];
 51     }
 52 }
 53 
 54 Wine::Wine(const char *l, int y) {
 55     label = l;
 56     numofyears = y;
 57     year_bots.first = ArrayInt(numofyears);
 58     year_bots.second = ArrayInt(numofyears);
 59 }
 60 
 61 Wine::~Wine() {
 62 
 63 }
 64 
 65 void Wine::GetBottles() {
 66     using namespace std;
 67     for (int i = 0; i < numofyears; ++ i) {
 68         cout << "#" << i << " year: ";
 69         cin >> year_bots.first[i];
 70         cout << "#" << i << " bottles: ";
 71         cin >> year_bots.second[i];
 72     }
 73     cout << "finished" << endl;
 74 }
 75 
 76 std::string &Wine::Label() {
 77     return label;
 78 }
 79 
 80 int Wine::sum() const {
 81     return year_bots.second.sum();
 82 }
 83 
 84 void Wine::show() const {
 85     using namespace std;
 86     cout << "year	bottles" << endl;
 87     for (int i = 0; i < numofyears; ++ i)
 88         cout << year_bots.first[i] << "	" << year_bots.second[i] << endl;
 89 }
 90 
 91 
 92 // run
 93 
 94 void ch14_1() {
 95     using namespace std;
 96     cout << "enter name of wine: ";
 97     char lab[50];
 98     cin.getline(lab, 50);
 99     cout << "enter number of years: ";
100     int yrs;
101     cin >> yrs;
102 
103     Wine holding(lab, yrs);
104     holding.GetBottles();
105     holding.show();
106 
107     const int YRS = 3;
108     int y[YRS] = {1993, 1995, 1998};
109     int b[YRS] = {48, 60, 72};
110     Wine more("Gushing Grape Red", YRS, y, b);
111     more.show();
112     cout << "total bottles for " << more.Label() << ": " << more.sum() << endl;
113     cout << "bye" << endl;
114     return;
115 }