Reverse string.

reverse.cpp

#include <iostream>
#include <string>
using namespace std;

void rev(string &x){
    int j = x.length()-1;

    for( int i = 0; i < x.length()/2; ++i){
        swap(x[i], x[j--]); 
    }
}

int main(){

    string d;
    getline(cin, d);
    cout << d << endl;
    rev(d);
    cout << d << endl;
    cin.get();
    return 0;
}