四则运算
package 一百; import java.io.BufferedReader; import java.io.File; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.FileReader; import java.io.IOException; import java.io.OutputStreamWriter; import java.util.Scanner; public class Build { @SuppressWarnings("resource") public static void main (String[] args)throws IOException{ File file = new File("D:/java/eclipse/100道题/Test.txt"); if(!file.getParentFile().exists()){ //如果文件的目录不存在 file.getParentFile().mkdirs(); //创建目录 } FileOutputStream fis=new FileOutputStream(file); OutputStreamWriter output = new OutputStreamWriter(fis); int[] answer=new int[100]; for (int i = 0; i < 100; i++) { int t = 0; String strz = ""; int x=(int)(Math.random()*100)+1; int y=(int)(Math.random()*100)+1; int z=(int)(Math.random()*100)+1; if( z<=15 ) { strz = "+"; if ((x+y) > 100) {//相加结果小于等于100 x = x / 2; y = y / 2; } answer[i]=x+y; } if( z>15 && z<=30 ) { strz = "-"; if( x < y ){//减数大于被减数 t = y; y = x; x = t; } answer[i]=x-y; } if( z>30 && z<=45) {//两个个位数相乘 strz = "×"; x = x % 10; y = y % 10; answer[i]=x*y; } if( z>45 ) { strz = "÷"; y = ( y % 10 ) + 1;//除数不能为0 if( x % y !=0){//余数不为0 strz = "-"; if( x < y ){//减数大于被减数 t = y; y = x; x = t; } answer[i]=x-y; } else{ answer[i]=x/y; } } String strx = String.valueOf( x ); String stry = String.valueOf( y ); String ques = strx + strz + stry + "="; output.write(ques+"\r\n"); } output.close(); File file1=new File("D:/java/eclipse/100道题/Test.txt"); int i=0; int score=0; if(file1.exists()){ try{ FileReader fileReader = new FileReader(file1); BufferedReader br = new BufferedReader(fileReader); String lineContent = null; while((lineContent = br.readLine())!=null){ System.out.println(lineContent); Scanner input = new Scanner(System.in); int a=input.nextInt(); if(a==answer[i]) { System.out.println("回答正确!"); score++; } else { System.out.println("回答错误! 答案是"+answer[i]); } i++; } br.close(); fileReader.close(); } catch (FileNotFoundException e1) { System.out.println("no this file");//文件不存在抛异常 e1.printStackTrace(); } catch (IOException e1) { System.out.println("io exception"); e1.printStackTrace(); } } System.out.println("分数为:"+score); } }
用了将近四节课,主要是核对答案时出现错误,数组引用不出来。这次测试让我发现许多自己知识的盲点,以后还会更加努力的。