/**
 * Class that simulates drawing two marbles from a jar.
 *   @author Dave Reed 
 *   @version 4/7/08
 */
public class PuzzleOne{
	private int numPairs;

	/**
	 * Constructs a MarbleTester object.
	 *   @param exp the number of marble drawing experiments to conduct.
	 */
	public PuzzleOne(int exp) {
		this.numPairs = exp;
	}

	/**
	 * Repeatedly draws two marbles and keeps track of how often they are the same color.
	 *   @param black the number of black marbles in the jar
	 *   @param white the number of white marbles in the jar
	 *   @return the percentage of times that the drawn marbles were the same color
	 */
	public double simulate(int black, int white) {
		if (black + white < 2 || this.numPairs == 0) {
		    return 0.0;
		}
		else {
            MarbleJar jar = new MarbleJar(black, white);
            
            int numSame = 0;
		    for (int i = 0; i < numPairs; i++) {
		        String marble1 = jar.drawMarble();
		        String marble2 = jar.drawMarble();
		        if (marble1.equals(marble2)) {
		            numSame++;
		        }
		        jar.addMarble(marble1);
		        jar.addMarble(marble2);
		    }
		    
		    return 100.0*numSame/this.numPairs;
		}    
	}
}