遞歸算法查找最大子序列——類名字取的不太好

package Algorithm;
import java.io.*;
import java.util.Random;

public class Algorithm_MaxSequence 
{
		public static void main(String[] ars)
		{
			ReadFileData readFileData = new ReadFileData(20);
			readFileData.readTxtData();
			readFileData.FindMaxSequence();
			readFileData.getResult();
		}
}

class ReadFileData
{
	int[] arrayNumber;
	int length;
	int maxValue;
	ReadFileData(int len)
	{
		this.length = len;
		arrayNumber = new int[this.length];
		this.maxValue = 0;
	}
	
	public void readTxtData()
	{
		
		String filepath = System.getProperty("user.dir");
		filepath+="\\maxsequence.txt";		
		try 
		{
			File file = new File(filepath);
			FileReader fr = new FileReader(file);
			BufferedReader bReader = new BufferedReader(fr);
			int count=0;
			while(bReader.ready()&&count<this.length)
			{
				arrayNumber[count]=Integer.valueOf(bReader.readLine());				
				System.out.println(arrayNumber[count]);
				count++;
			}	
			/*for(int i=0;i<this.length;i++)
			{
				System.out.println(arrayNumber[i]);
			}*/
			bReader.close();
			fr.close();
		} 
		catch (Exception e) 
		{
			e.printStackTrace();
		}
	}
	public void getResult() 
	{
		System.out.println("maxSequence= "+this.maxValue);
	}
	public void FindMaxSequence()
	{
		this.maxValue = maxSumRecuse(arrayNumber, 0, this.length-1);
	}
	
	public int maxSumRecuse(int[] a, int left,int rigth)
	{
		if(left==rigth)
		{
			if(a[left]>0)
				return a[left];
			else
				return 0;
		}		
		int center = (left+rigth)/2;
		int maxLeftSum = maxSumRecuse(a, left, center);
		int maxRightSum = maxSumRecuse(a, center+1, rigth);
		int maxLeftBorderSum =0,leftBorderSum =0;
		for(int i=center;i>=left;i--)
		{
			leftBorderSum+=a[i];
			if(leftBorderSum>maxLeftBorderSum)
				maxLeftBorderSum = leftBorderSum;
		}
		int maxRightBorderSum=0,rightBorderSum=0;
		for(int i =center+1;i<=rigth;i++)
		{
			rightBorderSum+=a[i];
			if(rightBorderSum>maxRightBorderSum)
				maxRightBorderSum = rightBorderSum;
		}
		return max3(maxLeftSum,maxRightSum,maxLeftBorderSum+maxRightBorderSum);
	}
	public int max3(int maxleftsum,int maxrightsum,int maxbordersum) 
	{
		return maxleftsum>maxrightsum ? maxleftsum:(maxrightsum<maxbordersum ? maxbordersum:maxrightsum);
	}	
}


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