空きが必要ないように実行する必要があります

Question

各プログラム間にスペースを必要とせずに実行できるようにするには、このプログラムが必要です。今のところ、このコードは、入力されたすべての文字の間にスペースがある場合、空白なしで実行されるように実行する必要があります。

public class InfixEval { 

Stack<String> operandsStk; //for operands 
Stack<Character> operatorsStk;//for operators +,-,*,/,(,) 
InfixEval() 
{ 
    //instantiate the stacks 
    operandsStk=new Stack<String>(); 
    operatorsStk=new Stack<Character>(); 
} 
//evaluates and returns the result 
public int evaluate(String exp) throws ArithmeticException 
{ 
    boolean fail=false; 
    try 
    { 
     //tokenize the expression 
    String tokens[]=exp.split(""); 
    for(int i=0;i<tokens.length;i++) 
    { 
     //if it is an operand push it onto the operand stack 
     if(!tokens[i].equals("+")&& !tokens[i].equals("*")&&!tokens[i].equals("-") 
        &&!tokens[i].equals("/") && !tokens[i].equals("(")&&!tokens[i].equals(")")) 
     { 
       operandsStk.push(tokens[i]); 
     } 
     //if it is a left parenthesis 
     else if(tokens[i].equals("(")) 
     { 
       //push it onto the operator stack 
       operatorsStk.push((Character)tokens[i].charAt(0)); 
     } 
     //it is a right parenthesis 
     else if(tokens[i].equals(")")) 
     { 
       //while top of the operator stack is not a left parenthesis 
       while(operatorsStk.peek()!='(') 
       { 
        // pop two operands and an operator 
        int x=Integer.parseInt(operandsStk.pop()); 
        int y=Integer.parseInt(operandsStk.pop()); 
        char opr=operatorsStk.pop(); 
        // perform the calculation 
        int result=0; 
        if (opr=='+') 
        { 
         result= y+x; 
         //push the result onto the operand stack  
         operandsStk.push(result+""); 
        } 
        else if(opr=='-') 
        { 
         result= y-x; 
         //push the result onto the operand stack 
         operandsStk.push(result+""); 
        } 
        else if(opr=='*') 
        { 
         result= y*x; 
         //push the result onto the operand stack 
         operandsStk.push(result+""); 
        } 
        else if(opr=='/') 
        { 
         result=y/x; 
         //push the result onto the operand stack 
         operandsStk.push(result+""); 
        } 

       } 
       //pop top of the operator stack and ignore it 
       operatorsStk.pop(); 
     } 
     //if it is an operator 
     else if(tokens[i].equals("+")||tokens[i].equals("-") 
        ||tokens[i].equals("*")||tokens[i].equals("/")) 
     { 
       //while the operator stack is not empty and   
       //the operator at the top of the stack has higher 
       //or the same precedence than the current operator 
       while(!operatorsStk.empty()&&hasHigherPrecedence(operatorsStk.peek(),tokens[i].charAt(0))) 
       { 
        //pop two operands 
        int x=Integer.parseInt(operandsStk.pop()); 
        int y=Integer.parseInt(operandsStk.pop()); 
        char opr=operatorsStk.pop(); 
        //perform the calculation 
        int result=0; 
        if (opr=='+') 
        { 
         result= y+x; 
         //push the result onto the operand stack 
         operandsStk.push(result+""); 
        } 
        else if(opr=='-') 
        { 
         result= y-x; 
         //push the result onto the operand stack 
         operandsStk.push(result+""); 
        } 
        else if(opr=='*') 
        { 
         result= y*x; 
         //push the result onto the operand stack 
         operandsStk.push(result+""); 
        } 
        else if(opr=='/') 
        { 
         result=y/x; 
         //push the result onto the operand stack 
         operandsStk.push(result+""); 
        } 
       } 

       operatorsStk.push(tokens[i].charAt(0)); 
     } 
    } 
    //while the operator stack is not empty 
    while(!operatorsStk.empty()) 
    { 
     // pop two operands and an operator 
     int x=Integer.parseInt(operandsStk.pop()); 
     int y=Integer.parseInt(operandsStk.pop()); 
     char opr=operatorsStk.pop(); 
     //perform the calculation 
     int result=0; 
     if (opr=='+') 
     { 
       result= y+x; 
       // push the result onto the operand stack 
       operandsStk.push(result+""); 
     } 
     else if(opr=='-') 
     { 
       result= y-x; 
       // push the result onto the operand stack 
       operandsStk.push(result+""); 
     } 
     else if(opr=='*') 
     { 
       result= y*x; 
       // push the result onto the operand stack 
       operandsStk.push(result+""); 
     } 
     else if(opr=='/') 
     { 
       result=y/x; 
       // push the result onto the operand stack 
       operandsStk.push(result+""); 
     } 
    } 
    } 
    catch(EmptyStackException e) 
    {   
     //if an error occurs 
     fail=true; 
    } 
    if(fail==false) 
     //the final result is at the top of the operand stack and return it 
     return Integer.parseInt(operandsStk.pop()); 
    else 
     return -1; 
} 
//returns true, if the top has high precedence than current 
boolean hasHigherPrecedence(char top, char current) 
{ 
    int topPre=-1; 
    int curPre=-1; 
    if(top == '+' || top == '-') 
    { 
     topPre=0; 
    } 
    if(top == '*' || top == '/' || top== '%') 
    { 
     topPre=1; 
    } 
    if(current == '+' || current == '-') 
    { 
     curPre=0; 
    } 
    if(current == '*' || current == '/') 
    { 
     curPre=1; 
    } 
    if(topPre>=curPre) 
     return true; 
    else 
     return false; 
} 


} 

Answer 1

は、この行をよく見てくださいありがとう：あなたはトークンに行を分割するために使用されている区切り文字です

String tokens[]=exp.split(""); 

何？