算法题1

给你10分钟时间，根据上排给出十个数，在其下排填出对应的十个数要求下排每个数都是先前上排对应那个数在下排十个数中出现的次数。

上排的十个数如下： 

  　【0，1，2，3，4，5，6，7，8，9】 

==============================================================================

import java.util.Arrays;

public class Number {
	private int[] top;
	private int[] bottom;
	private int length;
	private boolean success;
	
	public Number(int length){
		this.length=length<7?7:length;		//length<6无解
		this.success = false;
		this.top=new int[this.length];
		this.bottom=new int[this.length];
		for(int i=0;i<this.length;i++)
			top[i]=i;	
		
	}
	
	private int getFrequecy(int num) {//// num在bottom[]中出现的次数
        int count = 0;
        for (int i = 0; i < this.length; i++) {
            if (this.bottom[i] == num)
                count++;
        }
        return count;
    }
	
	// set next bottom　　
    private void setNextBottom() {
        boolean reB = true;
        for (int i = 0; i < this.length; i++) {
            int frequecy = getFrequecy(this.top[i]);//top[i]在bottom[]的出现次数
            if (this.bottom[i] != frequecy) {//若bottom[i]不等于frequency
                this.bottom[i] = frequecy;//修正
                reB = false;
            }
        }
        this.success = reB;
    }
    
	public int[] getBottom() {
        int i = 0;
        System.out.println("初始bottom："+toString());
        while (!this.success) {
            i++;
            setNextBottom();
            System.out.println("修正" + i + "次得到结果:"+toString());
        }
        
        return this.bottom;
    }

	@Override
	public String toString() {
		return "[success="+success + ",bottom=" + Arrays.toString(bottom) + "]";
	}
}

 运行：

	@Test
	public void testNumber() {
		Number que=new Number(10);
		que.getBottom(); 		
	}

 结果如下：

 

初始bottom：[success=false,bottom=[0, 0, 0, 0, 0, 0, 0, 0, 0, 0]]

 

修正1次得到结果:[success=false,bottom=[10, 0, 0, 0, 0, 0, 0, 0, 0, 0]]

 

修正2次得到结果:[success=false,bottom=[9, 0, 0, 0, 0, 0, 0, 0, 0, 1]]

 

修正3次得到结果:[success=false,bottom=[8, 1, 0, 0, 0, 0, 0, 0, 1, 0]]

 

修正4次得到结果:[success=false,bottom=[7, 2, 1, 0, 0, 0, 0, 1, 0, 0]]

 

修正5次得到结果:[success=false,bottom=[6, 2, 1, 0, 0, 0, 1, 0, 0, 0]]

 

修正6次得到结果:[success=true,bottom=[6, 2, 1, 0, 0, 0, 1, 0, 0, 0]]