java - Java 数组中的一堆元素

Question

我需要一些帮助来计算数组中相邻元素的数量。

假设我有 4 个整数数组。

myArray = {1, 1, 1, 1}
myArray2 = {5, 6, 7, 8, 7, 1, 10, 11, 12};
myArray3 = {5, 6, 7, 7, 8, 1, 10, 11, 12};
myArray4 = {5, 6, 7, 7, 8, 1, 10, 11, 11, 11, 12};

我想计算这些数组中元素的数量。

期望的输出应该是:

myArray => 1 (1 bunch of adjacent element "1")
myArray2 => 0 (no adjacent element)
myArray3 => 1 (1 bunch of adjacent  element "7")
myArray4 => 2 (2 bunches of adjacent elements "7" and "11")

我可以计算相邻元素的数量，但不能计算成串的数量。

这是我编写的代码:

import acm.program.ConsoleProgram;

public class project extends ConsoleProgram{
    public void run ()
    {
        int[] myArray = {1, 1, 1, 1};
        int[] myArray2 = {5, 6, 7, 8, 7, 1, 10, 11, 12};
        int[] myArray3 = {5, 6, 7, 7, 8, 1, 10, 11, 12};
        int[] myArray4 = {5, 6, 7, 7, 8, 1, 10, 11, 11, 11, 12};        

        println("myArray -> " + countBunches(myArray));
        println("myArray2 -> " + countBunches(myArray2));
        println("myArray3 -> " + countBunches(myArray3));
    }

    public int countBunches(int[] myArray)
    {   
        int count = 0;
        int saveIndex;
        int saveContent;

        for(int i = 0; i<myArray.length; i++)
        {
            if(i == 0)
            {
                saveContent = myArray[i];
            }
            else
            {
                saveContent = myArray[i-1];
                if(saveContent == myArray[i])
                {

                    saveContent = myArray[i];
                    saveIndex = i;
                    count++;
                    println(myArray[saveIndex] + " repatingb" + saveIndex + ". element");
                }
                else
                {
                    saveContent = myArray[i];
                }
            }
        }   

        return(count);
    }
}

Answer 1

问题在于，每次一个元素与最后一个元素匹配时，您都会进行计数。因此，如果连续有 3 个相同的项目，则算作 2，而不是 1。

一种方法是跟踪最后一项以及它是否匹配:

public int countBunches(int[] myArray)
{   
    int count = 0;
    int lastItem;
    boolean lastItemMatched;

    for(int i = 0; i<myArray.length; i++)
    {
        if(i == 0)
        {
            lastItem = myArray[0];
            lastItemMatched = false;
        }
        else
        {
            if(lastItem == myArray[i])
            {
                if(!lastItemMatched)
                {
                    count++;
                }

                lastItemMatched = true;
            } else {
                lastItemMatched = false;
            }

            lastItem = myArray[i];
        }
    }   

    return count;
}