VC6 の string

string str0 = "aaaaa";
string str1 = str0;
string str2 = str0.substr();
string str3 = string( str0.substr() );

if( str0.c_str() == str1.c_str() == str2.c_str() == str3.c_str() ){
    printf( "equal" );
}else{
    printf( "non equal" );
}

equal

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