extendmath.java

一个J2ME游戏,单机玩拼图游戏 ,游戏难度分为简单、一般、困难。简单是把一张图片分成了4块

package util;

/**
 * Created by IntelliJ IDEA.
 * User: robai
 * Date: 2007-2-26
 * Time: 15:15:12
 * To change this template use File | Settings | File Templates.
 */
public class ExtendMath {

    public int fn(int m, int n) {
        int r = 0;
        for (r = m; 0 != r % n; r += m) ;
        return r;
    }

    /* 两个数的最大公约数 */
    public int gcd(int a, int b) {
        if (a < b) {
            int temp = a;
            a = b;
            b = temp;
        }
        if (0 == b)//the base case
            return a;
        if (a % 2 == 0 && b % 2 == 0)//a and b are even
            return 2 * gcd(a / 2, b / 2);
        if (a % 2 == 0)// only a is even
            return gcd(a / 2, b);
        if (b % 2 == 0)// only b is even
            return gcd(a, b / 2);

        return gcd((a + b) / 2, (a - b) / 2);// a and b are odd

    }

    public int getGreatestCommonDivisor(int long1, int long2) {
        int bOne;
        int sOne;

        if (long1 < long2) {
            bOne = long1;
            sOne = long2;
        } else {
            bOne = long2;
            sOne = long1;
        }

        if (bOne % sOne == 0) {
            return sOne;
        }

        int t = sOne / 2;
        for (int i = t; i > 1; i--) {
            if (bOne % i == 0 && sOne % i == 0) {
                return i;
            }
        }

        return 1;
    }

    public static void main(String[] argsp) {
        ExtendMath math = new ExtendMath();
        System.out.println("64,4最大公约数:" + math.gcd(64, 4));
    }

}