C++primer 12.2.1節練習

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練習12.23

字串常量

 1 #include <iostream> 2 #include <string> 3  4 using namespace std; 5  6 int main() 7 { 8     char a[] = "hello"; 9     char b[] = "world";10     char * pa = new char[10];11     pa = a;12     for (auto i = 0; i != 5; ++i)13         cout << pa[i];14     cout << endl;15     for (auto i = 0,j = 5; i != 5; ++i, ++j)16     {17         pa[j] = b[i];18     }19     for (auto i = 0; i != 10; ++i)20         cout << pa[i];21     cout << endl;22     system("pause");23     return 0;24 }

string對象

 1 #include <iostream> 2 #include <string> 3  4 using namespace std; 5  6 int main() 7 { 8     string str1; 9     string str2;10     while (cin >> str1 >> str2)11     {12         string * str = new string[50];13         *str = str1 + str2;14         cout << *str << endl;15         delete[] str;16     }17     system("pause");18     return 0;19 }

 

練習12.24

 1 #include <iostream> 2 #include <string> 3  4 using namespace std; 5  6 int main() 7 { 8     string str1; 9     while (cin >> str1)10     {11         char * str = new char[str1.size()];12         for (auto i = 0; i != str1.size(); ++i)13             str[i] = str1[i];14         for (auto i = 0; i != str1.size(); ++i)15             cout << str[i];16         cout << endl;17         delete[] str;18     }19     system("pause");20     return 0;21 }

可以使用輸入的字串的長度來動態分配字元長度；

練習12.25

1 delete[] pa;

 

C++primer 12.2.1節練習