zoj 1003

http://blog.csdn.net/cxiaokai/article/details/6852706

抄袭上述算法：

通过每个数只使用一次，来检测是否存在相容解。堆栈最深为100，步骤数 100！

 输入结束的判断还蛋疼的不能用hasnext() ..

import java.util.Scanner;

public class Main {
    static boolean flag = false;

    static boolean check(int b, int s, int n) {
        for (int i = n; i > 1; i--) {
            if (s % i == 0 && check(b, s / i, i - 1))
                return true;
            if (b % i == 0 && check(b / i, s, i - 1))
                return true;
        }

        if (s == 1) {
            flag = true;
        }
        if (!flag) {
            return true;
        }
        if (s == 1 && b == 1) {
            return true;
        } else {
            return false;
        }
    }

    public static void main(String[] args) {
        int a, b;
        Scanner sc = new Scanner(System.in);
        while (sc.hasNextInt()) {
            a = sc.nextInt();
            b = sc.nextInt();
            flag = false;
            int small = a > b ? b : a;
            int big = a > b ? a : b;

            if (!check(big, small, 100)) {
                System.out.println(small);
            } else {
                System.out.println(big);
            }
        }
    }
}

 

 

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以下是我没想完的想法

我想通过获取两个数的乘积形式，枚举所有相同因子组合检测是否存在相容。但是在如何枚举上不知道如何去做。

胎死腹中、、

import java.util.Scanner;

public class Main {
    /**
     * 获得乘积形式，如果有因子大于100，直接返回false
     * 
     * @param chain
     * @param num
     * @return
     */
    static boolean getChain(int[] chain, int num) {
        int[] primes = new int[] { 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37,
                41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97 };
        int pp = 0;
        while (num != 1) {
            if (num % primes[pp] == 0) {
                num /= primes[pp];
                chain[primes[pp]]++;
                pp = 0;
            } else {
                if (pp == primes.length - 1) {
                    return false;
                }
                pp++;
            }
        }

        return true;
    }

    public static void main(String[] args) {
        int[] hChain = new int[101];
        int[] lChain = new int[101];
        int[] comChain = new int[101];
        int higher, lower, tmp;
        boolean hf = false, lf = false;
        Scanner sc = new Scanner(System.in);

        higher = sc.nextInt();
        lower = sc.nextInt();

        if (higher < lower) {
            tmp = higher;
            higher = lower;
            lower = tmp;
        }

        hf = getChain(hChain, higher);
        lf = getChain(lChain, lower);

        if (lf && hf) {
                //枚举组合
        } else if (!hf && lf) {
            System.out.println(lf);
        } else if (!lf) {
            System.out.println(hf);
        }
    }
}