Java 输出不正确

当我做不同的组合，比如d-c+a+b，它会给我一个精确的数字，比如118.0。有人能告诉我在我的代码中我的计算哪里错了吗。。 多谢各位

ValVarPairs.txt包含以下数字->a=100、b=5、c=10、d=13 这是我编的代码

package com.ecsgrid;

import java.io.*;

public class testC {

public static void main(String[] args) {
  int i = 0,j = 0;
  double result, values[] = new double[4];
  char k, operators[] = new char[3];
  for (i = 0; i <= 2; i++) 
    operators[i] = '+';      // default is to add the values

  File myfile;
  StreamTokenizer tok;
  BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
  String InputText;

  i = 0;
  try {
    myfile = new File("C:\\VarValPairs.txt");
    tok = new StreamTokenizer(new FileReader(myfile));  
    tok.eolIsSignificant(false);

    while ((tok.nextToken() != StreamTokenizer.TT_EOF) && (i <= 3)){
      if ((tok.ttype == StreamTokenizer.TT_NUMBER))
        values[i++] = tok.nval;
      }
  }
  catch(FileNotFoundException e) { System.err.println(e);  return; }
  catch(IOException f) { System.out.println(f); return; }

  System.out.println("Enter letters and operators:");

  try {
    InputText = in.readLine(); 
  }  
  catch(IOException f) { System.out.println(f); return; }

  for (i = 0; i < InputText.length(); i++)
  {
     k = InputText.charAt(i);
     if ((k == '+') || (k == '-'))
     {
        if (j <= 2) operators[j++] = k;   
     }
  } 

  result = values[0];
  for (i = 0; i <= 2; i++){
   if (operators[i] == '+')
     result = result + values[i+1];  
   else
     result = result - values[i+1];
  }
  System.out.println(result);  
 }
}

package com.ecsgrid；
导入java.io.*；
公共类testC{
公共静态void main（字符串[]args）{
int i=0，j=0；
双精度结果，值[]=新的双精度[4]；
字符k，运算符[]=新字符[3]；
对于（i=0；i，如果您的输入是
-++

您从不分析顺序或a、b、c和d。您总是假定顺序为a->b->c->d

因此，d-c+a+b将是：a-b+c+d，这与您提供的输出一致（100-5+10+13=118）

OP代码

for（i=0；i如果（j让我们调试一下，添加一些系统输出

这是您将看到的每一步
100.0 - 5.0
95.0 +  10.0
105.0 + 13.0
118.0

值数组是{100,5,10,13}，运算符数组是{-，+，+}

您还没有映射a=100、b=5、c=10、d=13，除非您映射它们，然后使用基于非操作数输入键的映射来解析操作数，否则它将不起作用

所以，如果我使用角色的int值，我就可以这样翻译它

import java.io.*;

public class TestC {

    public static void main(String[] args) {
        int i = 0, j = 0;
        double result, values[] = new double[4];
        char k, operatorsAndOperands[] = new char[3];
        for (i = 0; i <= 2; i++)
            operatorsAndOperands[i] = '+'; // default is to add the values

        File myfile;
        StreamTokenizer tok;
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        String InputText;

        i = 0;
        try {
            myfile = new File("C:\\VarValPairs.txt");
            tok = new StreamTokenizer(new FileReader(myfile));
            tok.eolIsSignificant(false);

            while ((tok.nextToken() != StreamTokenizer.TT_EOF) && (i <= 3)) {
                if ((tok.ttype == StreamTokenizer.TT_NUMBER))
                    values[i++] = tok.nval;
            }
            for (int l = 0; l < values.length; l++) {
                System.out.println(values[l]);
            }
        } catch (FileNotFoundException e) {
            System.err.println(e);
            return;
        } catch (IOException f) {
            System.out.println(f);
            return;
        }

        System.out.println("Enter letters and operators:");

        try {
            InputText = in.readLine().toUpperCase();
        } catch (IOException f) {
            System.out.println(f);
            return;
        }

        if(InputText.length() > 0){
            operatorsAndOperands = new char[InputText.length()];
        } else {
            System.out.println("No Operations specified");
            return;
        }
        for (i = 0; i < InputText.length(); i++) {
            k = InputText.charAt(i);
            operatorsAndOperands[j++] = k;
        }

        result = 0; 
        for (i = 0; i < operatorsAndOperands.length; i++) {
            System.out.println(operatorsAndOperands[i] + " " + (int)operatorsAndOperands[i]);
            if(i+1<operatorsAndOperands.length)
                System.out.println(operatorsAndOperands[i+1]);
            switch(operatorsAndOperands[i]){
            case '+':
                if(operatorsAndOperands[i+1] != '+' && operatorsAndOperands[i+1] != '-'){
                    result+=values[(int)operatorsAndOperands[i+1] - (int)'A'];
                    i++;
                }
                break;
            case '-':
                if(operatorsAndOperands[i+1] != '+' && operatorsAndOperands[i+1] != '-'){
                    result-=values[(int)operatorsAndOperands[i+1] - (int)'A'];
                    i++;
                }
                break;
            default:
                result = values[(int)operatorsAndOperands[i] - (int)'A'];
                break;
            };
            System.out.println(result);
        }
        System.out.println(result);
    }
}

import java.io.*；
公共类TestC{
公共静态void main（字符串[]args）{
int i=0，j=0；
双精度结果，值[]=新的双精度[4]；
字符k，运算符和操作数[]=新字符[3]；
对于（i=0；i）如果K不是，我如何选择哪一个是运算符t@soupi7在某个时刻，k将是每个字符。您现在正在遍历整个字符串，查找运算符，并将它们放入数组中。在此过程中，如果k不是运算符（If语句上的else）然后你需要实现某种逻辑来保存它是哪个字符。在第一次迭代中，k将是d。把“d”放在数组中，你知道它是第一个。我把d放在数组中，同样的问题仍然可以。你能重写它吗？这样它会告诉我k将被d和d放在数组中吗？谢谢cruncher，我已经解决了它。一种方法是to使用Hashmap将a映射到100 b到5等，或使用字符的int值获取运算符值，请参见我的编辑。非常感谢您的帮助，我已经在您的帮助下解决了此问题。学会使用调试程序不要再发布类似的重复项。
import java.io.*;

public class TestC {

    public static void main(String[] args) {
        int i = 0, j = 0;
        double result, values[] = new double[4];
        char k, operatorsAndOperands[] = new char[3];
        for (i = 0; i <= 2; i++)
            operatorsAndOperands[i] = '+'; // default is to add the values

        File myfile;
        StreamTokenizer tok;
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        String InputText;

        i = 0;
        try {
            myfile = new File("C:\\VarValPairs.txt");
            tok = new StreamTokenizer(new FileReader(myfile));
            tok.eolIsSignificant(false);

            while ((tok.nextToken() != StreamTokenizer.TT_EOF) && (i <= 3)) {
                if ((tok.ttype == StreamTokenizer.TT_NUMBER))
                    values[i++] = tok.nval;
            }
            for (int l = 0; l < values.length; l++) {
                System.out.println(values[l]);
            }
        } catch (FileNotFoundException e) {
            System.err.println(e);
            return;
        } catch (IOException f) {
            System.out.println(f);
            return;
        }

        System.out.println("Enter letters and operators:");

        try {
            InputText = in.readLine().toUpperCase();
        } catch (IOException f) {
            System.out.println(f);
            return;
        }

        if(InputText.length() > 0){
            operatorsAndOperands = new char[InputText.length()];
        } else {
            System.out.println("No Operations specified");
            return;
        }
        for (i = 0; i < InputText.length(); i++) {
            k = InputText.charAt(i);
            operatorsAndOperands[j++] = k;
        }

        result = 0; 
        for (i = 0; i < operatorsAndOperands.length; i++) {
            System.out.println(operatorsAndOperands[i] + " " + (int)operatorsAndOperands[i]);
            if(i+1<operatorsAndOperands.length)
                System.out.println(operatorsAndOperands[i+1]);
            switch(operatorsAndOperands[i]){
            case '+':
                if(operatorsAndOperands[i+1] != '+' && operatorsAndOperands[i+1] != '-'){
                    result+=values[(int)operatorsAndOperands[i+1] - (int)'A'];
                    i++;
                }
                break;
            case '-':
                if(operatorsAndOperands[i+1] != '+' && operatorsAndOperands[i+1] != '-'){
                    result-=values[(int)operatorsAndOperands[i+1] - (int)'A'];
                    i++;
                }
                break;
            default:
                result = values[(int)operatorsAndOperands[i] - (int)'A'];
                break;
            };
            System.out.println(result);
        }
        System.out.println(result);
    }
}