常用字符串string操作--find

常用字符串string操作--find

#include  < iostream >
#include  < string >
#include  < cctype >
#include  < vector >
#include  < algorithm >
#include  < iterator >

using namespace std;

int  main( int  argc, char **  argv[])
{
    string line1 = " We were her pride of 10 she named us: " ;
    string line2 = " Benjamin, Phoenix, the Prodigal " ;
    string line3 = " and perspicacious pacific Suzanne " ;
    string sentence  =  line1 + '   ' + line2 + '   ' + line3;
    
    string separator( "  \n\t:,\r\v\f " );
    vector < string >  longest,shortest;
     int  num  =   0 ;
    string::size_type startpos = 0 ,endpos = 0 ;
    string word;
     int  longLen = 0 ,shortLen =- 1 ,wordlen;
    
     while ((startpos = sentence.find_first_not_of(separator,endpos)) != string::npos)
    {
         ++ num;
        
        endpos = sentence.find_first_of(separator,startpos);
         if (endpos == string::npos)
        {
            wordlen  =  sentence.size() - startpos;
        }
         else
        {
            wordlen  =  endpos - startpos;
        }
        
        word.assign(sentence.begin() + startpos,sentence.begin() + wordlen + startpos);
        
        startpos  =  sentence.find_first_not_of(separator,endpos);
        
         if (shortLen ==- 1 )
        {
            shortLen = longLen = wordlen;
            shortest.push_back(word);
            longest.push_back(word);
            
             continue ;
        }
         if (shortLen == wordlen)
        {
            shortest.push_back(word);
        }
         if (shortLen > wordlen)
        {
            shortest.clear();
            shortest.push_back(word);
            shortLen  =  wordlen;
        }
         if (wordlen == longLen)
        {
            longest.push_back(word);
        }
         if (wordlen > longLen)
        {
            longest.clear();
            longest.push_back(word);
            longLen = wordlen;
        }    
    }
    
    cout << " Words: " << num << endl;
    cout << " Shortest: " << shortLen << endl;
    copy(shortest.begin(),shortest.end(),ostream_iterator < string > (cout, "   " ));
    cout << endl;
    cout << " Longest: " << longLen << endl;
    copy(longest.begin(),longest.end(),ostream_iterator < string > (cout, "   " ));
    cout << endl;
    
    system( " pause " );
     return   0 ;
}

#include  < iostream >
#include  < string >
#include  < cctype >
#include  < vector >
#include  < algorithm >
#include  < iterator >

using namespace std;

void  str_replace(string &  str, const  string &  src, const  string &  dst)
{
    string::size_type pos  =   0 ;
     int  srclen  =  src.size();
     int  dstlen  =  dst.size();
    
     while ((pos  =  str.find(src,pos)) != string::npos)
    {
         // str.replace(pos,srclen,dst);
        str.erase(pos,srclen);
        str.insert(pos,dst);
        pos += dstlen;
    }
}

int  main( int  argc, char **  argv[])
{
     // replace/erase/insert
    string str( " I like apple,what about you? apple tastes great! " );
    cout << str << endl;
    str_replace(str, " apple " , " banana " );
    cout << str << endl;
    
     // assign/append
    string q1( " When lilacs last in the dooryard bloom'd " );
    string q2( " The child is father of the man " );
    string sentence;
    
    sentence.assign(q2.begin(),q2.begin() + 13 );
    sentence.append(q1.substr(q1.find( " in " ), 15 ));
    cout << sentence << endl;
    
    system( " pause " );
     return   0 ;
}