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 工…