Since you know Java well, but C++ no so well, this assignment is to convert a Java program into a C++ program.

(For another comparison of C++ and Java, see the sieve program in Java and compare it to the sieve program in C++ in the text.)

Here's the program in Java. We'll discuss it in detail in class.

QueenDemo.java

public class QueenDemo
{
   public static void main (String [] args) {
     System.out.println("\nThe eight-queens problem is to find all possible");
     System.out.println("positions of eight queens so that none attack any other.");
     System.out.println("Here are the solutions to the 8-queens problem\n");
     // Create the first queen and the rest of the row of 8 queens
     Queen first = new Queen(8,1,null);
     // Try placing the first queen, then the rest in possible ranks in
     // their columns
     first.place();
   }
}

Queen.java

public class Queen
{
   private int size; // dimension of the board
   private int file; // the fixed file for this queen
   private int rank; // the variable rank for this queen
   private Queen left, right; // the neighboring queens

   /* Create yourself on a board of the specified size, in
   the specified file, and all the queens to your right, so that
   each queen knows its immediate neighbors */
   public Queen(int sizeIn, int fileIn, Queen leftIn) {
      size = sizeIn;
      file = fileIn;
      left = leftIn;
      if (size < file)
         right = new Queen(size, file+1, this);
   }

   /* Try placing yourself in all possible ranks */
   public void place() {
      for (rank=1; rank<=size; ++rank)
         if (file==1 || !left.attack(file,rank))
	    if (file1) left.print();
      System.out.print(" "+this);
      if (file==size) System.out.println();
   }

   /* Do you or any queens to your left attack this square? */
   private boolean attack(int f, int r) {
      return inSight(file,rank,f,r) || (file>1 && left.attack(f,r));
   }

   /* Are the two squares in sight of each other?  That is, are they
   on the same rank or in the same diagonal? It's assumed they're in
   different files */
   private static boolean inSight(int f1, int r1, int f2, int r2) {
      return r1==r2 || Math.abs(f1-f2)==Math.abs(r1-r2);
   }

   public String toString() {
      return "["+rank+","+file+"]";
   }
}

Here are the first few lines of output when you run the program, and the last line.

$ java QueenDemo

The eight-queens problem is to find all possible
positions of eight queens so that none attack any other.
Here are the solutions to the 8-queens problem

 [1,1] [5,2] [8,3] [6,4] [3,5] [7,6] [2,7] [4,8]
 [1,1] [6,2] [8,3] [3,4] [7,5] [4,6] [2,7] [5,8]
 [1,1] [7,2] [4,3] [6,4] [8,5] [2,6] [5,7] [3,8]
 [1,1] [7,2] [5,3] [8,4] [2,5] [4,6] [6,7] [3,8]
 [2,1] [4,2] [6,3] [8,4] [3,5] [1,6] [7,7] [5,8]
 [2,1] [5,2] [7,3] [1,4] [3,5] [8,6] [6,7] [4,8]
 [2,1] [5,2] [7,3] [4,4] [1,5] [8,6] [6,7] [3,8]
 [2,1] [6,2] [1,3] [7,4] [4,5] [8,6] [3,7] [5,8]
 ...
 [8,1] [4,2] [1,3] [3,4] [6,5] [2,6] [7,7] [5,8]
$

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