Test.java

package test;

import java.util.Random;

public class Test {

    public static void main(String[] args) throws Exception {

        int x = 100;
        int y = 10;
        int a = 5;
        int b = 15;

        decompose(x, y, a, b);

    }

    private static void decompose(int x, int y, int a, int b) throws Exception {

        if (!((x >= a * y) && (x <= b * y))) {
            throw new Exception("该题无解！");
        }

        int remainder = x - a * y;
        final int max = b - a;

//        System.out.println("个数=" + y);
//        System.out.println("余数=" + remainder);
//        System.out.println("最大值=" + max);

        //
        Random random = new Random();
        for (int i = 0; i < y - 1; i++) {
            int amount = 0;
            do {
                amount = random.nextInt(max + 1);
            } while (remainder - amount < 0 || remainder - amount > max * (y - i - 1)); // 保证后面的在区间内
            remainder -= amount;
            System.out.println(amount + a);
        }

        // 最后一个值
        System.out.println(remainder + a);

    }

}