ClimbTheLadder

/*
 *假设每一步可以爬一格或者两个梯子，爬一部n格梯子共有多少种方法
 *Created by chenkai on 2017/3/9.
 */
public class ClimbTheLadder {
    public static void main(String[] args) {
        System.out.printf("请输入梯子的格数(正整数)：");
        Scanner sc = new Scanner(System.in);
        long n=sc.nextLong();
        climb(n);
        climbTwo(n);
    }

    private static void climb(long n) {
        long count = 0;
        long time = System.currentTimeMillis();
        for (long i = 0; i <= n / 2; i++) {
            for (long k = 0; k <= (n - 2 * i); k++) {
                if (n == (k + 2 * i)) {
                    System.out.printf("需要爬%d次一格，%d次两格\n", k, i);
                    count++;
                }
            }
        }
        System.out.printf("共有%d种爬法", count);
        System.out.printf("共耗时:" + (System.currentTimeMillis() - time)+"\n");
    }

    private static void climbTwo(long n) {
        long count=0;
        long time = System.currentTimeMillis();
        for(long i=n;i>=0;i--){
            if ((n-i)%2==0){
                System.out.printf("需要爬%d次一格，%d次两格\n",i,n-i);
                count++;
            }
        }
        System.out.printf("共有%d种爬法", count);
        System.out.printf("共耗时:" + (System.currentTimeMillis() - time)+"\n");
    }
}