Pre and Post increment

pre_and_post_increment.cpp

#include <iostream>
using namespace std;

int preincrement(int & x){
  // Add one to x, and return the new value for x.
  x = x+1;
  return x;
}

int postincrement(int & x){
  // Copy x to a temporary variable, add one to x, and return the original value of x that's stored in temp.
  int temp = x;
  x = x+1;
  return temp;
}

int main(){
  // Initialize x to a silly value, like 42.
  int x = 42;
 
  // Well, x hasn't changed yet. Prints 42.
  cout << x << endl;
 
  // This will increment x and then return x: Prints 43.
  cout << preincrement(x) << endl;
 
  // Prints 43.
  cout << x << endl;
 
  // This will make a copy of x, increment x, and return x: Prints 43.
  cout << postincrement(x) << endl;
 
  // Prints 44
  cout << x << endl;
 
  return 0;
}