tsaiwn@magpie c++% cat -n string2 .cpp
     1  //string2.cpp  -- @CopyLeft by tsaiwn@csie.nctu.edu.tw
     2  // some useful member functions in the class string
     3  #include <string>
     4  #include <iostream>
     5  using namespace std;
     6  #include <string.h>
     7  int main()
     8  {
     9      string s("Hello here there!");
    10      string s2="Hello here there!";
    11      string t;
    12      t = s + " How R U doing?";
    13      cout << "t=" << t << endl;
    14      cout << "s2=" << s2 << endl;
    15      cout << "s=" << s << endl;
    16      cout << " (s==s2) == " << (s==s2) << endl;
    17      cout << " (s> s2) == " << (s> s2) << endl;
    18      cout << " (s< s2) == " << (s< s2) << endl;
    19      cout << " (s> t) == " << (s> t) << endl;
    20      cout << " (s< t) == " << (s< t) << endl;
    21      cout << "s.substr(1,3)=" << s.substr(1,3)<<endl;
    22      cout << "s.substr(6)=" << s.substr(6)<<endl;
    23      cout << "s.length()=" << s.length()<<endl;
    24      cout << "s.size()=" << s.size()<<endl;
    25      s.insert(2,"222");
    26      cout << "after \"s.insert(2,\"222\"); \n";
    27      cout << "s=" << s << endl;
    28      s.erase(2,2);
    29      cout << "after \"s.erase(2,2); \n";
    30      cout << "s=" << s << endl;
    31      cout << "s.find(\"e\") = "; cout << s.find("e") << endl;
    32      cout << "s.find_last_of(\"e\") = "; cout << s.find_last_of("e") << endl;
    33      cout << "s.find_last_of(\"here\") = ";
    34       cout << s.find_last_of("here") << endl;
    35      cout << "s.find_first_of(\"here\") = ";
    36       cout << s.find_first_of("here") << endl;
    37      cout << "string::npos==" << string::npos << endl;
    38      cout << "s.find(\"E\") = "; cout << s.find("E") << endl;
    39     string::iterator i;
    40      for(i= s.begin(); i < s.end(); i++){
    41         cout << "*i= " << *i << endl;
    42      }
    43  
    44     char * p;
    45      p = (char*)s.c_str();
    46      cout << "p=" << p << endl;
    47      cout << "strlen(p)=" << strlen(p) << endl;
    48      cout << "strchr(p, 'e') - p ==" <<  strchr(p,'e')  - p << endl;
    49    char *cs1="ABCDEFG", *cs2="ABCDE";
    50      cout << "cs1=" << cs1 << endl;
    51      cout << "cs2=" << cs2 << endl;
    52      cout << "strcmp(cs1, cs2) == " << strcmp("ABCDE", "ABCDE")<<endl;
    53  
    54  }
tsaiwn@magpie c++% g++ string2 .cpp
tsaiwn@magpie c++% ./a.out
t=Hello here there! How R U doing?
s2=Hello here there!
s=Hello here there!
 (s==s2) == 1
 (s> s2) == 0
 (s< s2) == 0
 (s> t) == 0
 (s< t) == 1
s.substr(1,3)=ell
s.substr(6)=here there!
s.length()=17
s.size()=17
after "s.insert(2,"222"); 
s=He222llo here there!
after "s.erase(2,2); 
s=He2llo here there!
s.find("e") = 1
s.find_last_of("e") = 16
s.find_last_of("here") = 16
s.find_first_of("here") = 1
string::npos==4294967295
s.find("E") = 4294967295
*i= H
*i= e
*i= 2
*i= l
*i= l
*i= o
*i=  
*i= h
*i= e
*i= r
*i= e
*i=  
*i= t
*i= h
*i= e
*i= r
*i= e
*i= !
p=He2llo here there!
strlen(p)=18
strchr(p, 'e') - p ==1
cs1=ABCDEFG
cs2=ABCDE
strcmp(cs1, cs2) == 0
tsaiwn@magpie c++% exit
exit