A program using a conditional

// Author: Karl Abrahamson
// Date:   01/12/00
//
// This program reads two integers and prints the larger of
// the two.

#include <iostream>
using namespace std;

///////////////////////////////////////////////////////////
//                   max
///////////////////////////////////////////////////////////
// max(x,y) returns the larger of x and y.
///////////////////////////////////////////////////////////

int max(int x, int y)
{
  if(x > y) {
    return x;
  }
  else {
    return y;
  }
}

///////////////////////////////////////////////////////////
//                   main
///////////////////////////////////////////////////////////

int main()
{
  int n,m;
  cout << "What numbers shall I use? ";
  cin >> n >> m;
  cout << "The larger of " << n << " and " << m
       << " is " << max(n,m) << endl;
  return 0;
}

Notes on the program

// Author: Karl Abrahamson
// Date:   01/12/00
//
// This program reads two integers and prints the larger of
// the two.

#include <iostream>
using namespace std;

///////////////////////////////////////////////////////////
//                   max
///////////////////////////////////////////////////////////
// max(x,y) returns the larger of x and y.
///////////////////////////////////////////////////////////

The conditional starts with if. Notice that there are parentheses around the condition. They are required.

int max(int x, int y)
{
  if(x > y) {
    return x;
  }
  else {
    return y;
  }
}

///////////////////////////////////////////////////////////
//                   main
///////////////////////////////////////////////////////////

int main()
{
  int n,m;
  cout << "What numbers shall I use? ";
  cin >> n >> m;
  cout << "The larger of " << n << " and " << m
       << " is " << max(n,m) << endl;
  return 0;
}