WaterAndJugProblem.java

package math;

import java.math.BigInteger;

/**
 * Created by gouthamvidyapradhan on 29/07/2017.
 * You are given two jugs with capacities x and y litres. There is an infinite amount of water supply available. You need to determine whether it is possible to measure exactly z litres using these two jugs.
 * <p>
 * If z liters of water is measurable, you must have z liters of water contained within one or both buckets by the end.
 * <p>
 * Operations allowed:
 * <p>
 * Fill any of the jugs completely with water.
 * Empty any of the jugs.
 * Pour water from one jug into another till the other jug is completely full or the first jug itself is empty.
 * Example 1: (From the famous "Die Hard" example)
 * <p>
 * Input: x = 3, y = 5, z = 4
 * Output: True
 * Example 2:
 * <p>
 * Input: x = 2, y = 6, z = 5
 * Output: False
 */
public class WaterAndJugProblem {
    /**
     * Main method
     *
     * @param args
     * @throws Exception
     */
    public static void main(String[] args) throws Exception {
        System.out.println(new WaterAndJugProblem().canMeasureWater(0, 0, 1));
    }

    public boolean canMeasureWater(int x, int y, int z) {
        if (x == y && y == z) return true;
        if (z > (x + y)) return false;
        BigInteger b1 = new BigInteger(String.valueOf(x));
        BigInteger b2 = new BigInteger(String.valueOf(y));
        BigInteger b3 = b1.gcd(b2);
        return b3.intValue() != 0 && (z % b3.intValue()) == 0;
    }
}