reverse char sequence

Bjarne Stroustrup “Programming Principles and Practice Using C++”
Chapter 8 Exercise 6
Using std_lib_facilities.h by Bjarne Stroustrup.

main.cpp main file

[code language=”cpp”]
// Philipp Siedler
// Bjarne Stroustrup’s PP
// Chapter 8 Exercise 6

#include "std_lib_facilities.h"

vector<string> myVec{ "a","b","c","d","e","f","g","h","i","j" };
vector<string> myVecRev;

class Rev {
public:
vector<string> v;
vector<string> vr;

Rev(vector<string>& _v, vector<string>& _vr) :v(_v), vr(_vr) {};
void reverse();
void reverseSame();
void printV(string);
void printVR(string);
};

void Rev::reverse() {
for (int i = 0; i < v.size(); i++) {
vr.push_back(v[(v.size() – 1) – i]);
}
}

void Rev::reverseSame() {
for (int i = 0; i < v.size() / 2; i++) {
string temp;
temp = v[i];
v[i] = v[(v.size() – 1) – i];
v[(v.size() – 1) – i] = temp;
}
}

void Rev::printV(string label) {
for (string x : v) {
cout << label << " " << x << "\n";
}
}

void Rev::printVR(string label) {
for (string x : vr) {
cout << label << " " << x << "\n";
}
}

int main()
try
{
string label = "l";

Rev rev(myVec, myVecRev);

cout << "First version:\n";

rev.reverse();
rev.printV(label);
rev.printVR(label);

cout << "Second version:\n";

rev.reverseSame();
rev.printV(label);

keep_window_open();
}
catch (runtime_error e) {
cout << e.what() << "\n";
keep_window_open();
}

catch (…) {
cout << "Exiting\n";
keep_window_open();
}
[/code]

Output:
First version:
l a
l b
l c
l d
l e
l f
l g
l h
l i
l j
l j
l i
l h
l g
l f
l e
l d
l c
l b
l a
Second version:
l j
l i
l h
l g
l f
l e
l d
l c
l b
l a
Please enter a character to exit