玩玩小程序

一、L的3.41次方+40000L的1.56次方=21780889，帮我算出L

解决方案，正常算，确实不会算，采用无限趋近法，得到近似值，编程采用递归

 

import java.io.BufferedReader;

import java.io.BufferedWriter;

import java.io.Console;

import java.io.File;

import java.io.FileReader;

import java.io.FileWriter;

import java.util.ArrayList;

import java.util.List;





public class Io {

	

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

		new Io().operate(1, 1000, 1);

		

		}

		

		private void operate(double min,double max,double add){

			boolean bool = true;

			List<Double> list = new ArrayList<Double>();

			List<Double> listSub = new ArrayList<Double>();

			double sub = 0;

			for(double i=min;i<max;i+=add){

				list.add(i);

				double result = Math.pow(i, 3.41) + Math.pow(i, 1.56)*40000;

				if((sub = Math.abs(result-21780889)) < 0.001){

					bool = false;

					break;

				}else{

					listSub.add(sub);

				}

			}

			if(bool){

				int pos = 0;

				for(int j=0;j<listSub.size()-1;j++){

					pos = j;

					if(listSub.get(j)<listSub.get(j+1)){

						break;

					}

				}

				operate(list.get(pos-1), list.get(pos+1), add/10);

			}else{

				System.out.println("最终结果："+list.get(list.size()-1)+"    "+sub);

			}

		}

}

 

二、

 

import java.io.BufferedReader;

import java.io.BufferedWriter;

import java.io.Console;

import java.io.File;

import java.io.FileReader;

import java.io.FileWriter;

import java.util.ArrayList;

import java.util.List;





public class Io {

	

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





		String path = "c:\\weibo.txt";

		String content = null;

		String account[];

		

		//read the txt;

		content = new Io().readTxt(path);

		

		// show all of the accounts on the screen

		account = content.split("#");

		for(int i=0,len=account.length;i<len;i++){

			System.out.println(account[i]);

		}

		

		// " " replace # and save in the floder

		content = content.replace("#", " ");

		new Io().writeTxt("c:\\chulihou.txt", content);  //chulihou.txt这出题人也够NB嗒

		

		//delete the floder

		File file = new File(path);

		file.delete();

	}

	

	private String readTxt(String path) throws Exception{

		StringBuffer string = new StringBuffer();

		String temp;

		BufferedReader in =new BufferedReader(new FileReader(path));

		while((temp = in.readLine()) != null){

			string.append(temp);

		}

		in.close();

		return string.toString();

	}

	

	private void writeTxt(String path, String content) throws Exception{

		FileWriter   fw=new   FileWriter( path ); 

		BufferedWriter   bw   =new   BufferedWriter(fw); 

		bw.write( content );

		bw.flush();

		bw.close();

		fw.close();

	}



}