debugging05.cpp

C++上机课的习题答案

// Chapter 5 of C++ How to Program
// Debugging Problem
//分别输入两个人的姓名和年龄，把第二个人的年龄加1后跟第一个人的姓名和年龄进行比较。
//注意指针和数组的使用，按值、按引用和按址传递参数给函数的区别和各自的使用。
//注意指针运算及cstring函数库中的字符串函数的使用。 
#include <iostream>

using std::cout;
using std::cin;
using std::endl;

#include <cstring>

void initialize( char [], int * );
void input( const char [], int & );
void print( const char *, const int );
void growOlder( const char [], int * );
bool comparePeople( const char *, const int *,
                    const char *, const int * );

int main()
{
   char name1[ 25 ]; 
   char name2[ 25 ];
   int age1;
   int age2;

   initialize( name1, &age1 );
   initialize( name2, &age2 );

   print( name1, *age1 );
   print( name2, *age2 );

   input( name1, age1 );
   input( name2, age2 );

   print( &name1, &age1Ptr );
   print( &name2, &age1Ptr );

   growOlder( name2, age2 );

   if ( comparePeople( name1, &age1, name2, &age2 ) )
      cout << "Both people have the same name and age"
           << endl;

   system("PAUSE");
   return 0;

} // end main

// function input definition（定义） 
void input( const char name[], int &age )
{
   cout << "Enter a name: ";
   cin >> name;

   cout << "Enter an age: ";
   cin >> age;
   cout << endl;

} // end function input

// function initialize definition
void initialize( char name[], int *age )
{
   name = "";
   age = 0;

} // end function initialize

// function print definition
void print( const char name[], const int age )
{
   cout << "The value stored in variable name is: "
        << name << endl
        << "The value stored in variable age is: "
        << age << endl << endl;

} // end function print

// function growOlder definition
void growOlder( const char name[], int *age )
{
   cout << name << " has grown one year older\n\n";
   *age++;

} // end function growOlder

// function comparePeople definition
bool comparePeople( const char *name1, const int *age1,
                    const char *name2, const int *age2 )
{
   return ( age1 == age2 && strcmp( name1, name2 ) );

} // end function comparePeople