Reverse string in c++

#include <iostream>
                                                #include <stdio>
                                                #include <conio>
                                                #include <string>


                                       char str[55];


                                     void main(void)
                                     {
                                             cout<<"Enter any string\t";gets(str);
                                             cout<<endl;
                                             cout<<"Your desire string is\t"<<str<<endl;
                                             cout<<"Reverse of Your string is\t";
                                             cout<<strrev(str);
                                     getch();}