InfixToPostfixConverter - Javascript

0-stack.js

class Stack {
  constructor() {
    this.arr = [];
  }
  pull() {
    return this.arr.pop();
  }
   
  peek(){
    return this.arr.slice(-1)[0];
  }

  push(el) {
    this.arr.push(el);
  }

  empty(){
    return this.arr.length == 0;
  }
}

1.js

class InfixToPostfixConverter {
  constructor( ) {
    this.operators = ['+', '-'];
  }
  
  convert(symbols) {
    var exit = [];
    var stack = new Stack(); 
    for (let symbol of symbols) {

      if (this._is_numeric(symbol)) {
        exit.push(symbol);
      } else if (this.operators.includes(symbol)) {
        stack.push(symbol);
      };

      while(!stack.empty()) {
        exit.push(stack.pull());
      }
    }
    return exit;
  }

  _is_numeric(str) {
    return /^\d+$/.test(str);
  }
}
var converter = new InfixToPostfixConverter( priority );
console.log(converter.convert(Array.from("1+2+3+4+5")).join(' '))

2.js

class InfixToPostfixConverter {
  constructor( priority ) {
    this.operators = ['+', '-'];
  }
  
  convert(symbols) {
    var exit = [];
    var stack = new Stack(); 
    for (let symbol of symbols) {

      if (this._is_numeric(symbol)) {
        exit.push(symbol);
      } else if (this.operators.includes(symbol)) {
        stack.push(symbol);
      } else if (symbol == '(') {
        stack.push('(');
      } else if (symbol == ')') {
        while(stack.peek() != '(') {
          exit.push(stack.pull());
        }
        stack.pull();
      }

      while(!stack.empty()) {
        exit.push(stack.pull());
      }
    }
    return exit;
  }

  _is_numeric(str) {
    return /^\d+$/.test(str);
  }
}

var converter = new InfixToPostfixConverter( priority );
console.log(converter.convert(Array.from("1+2+3+4+5")).join(' '))

3.js

var  priority = {
    '-': 1,
    '+': 1,
    '/': 2,
    '*': 2
};

class InfixToPostfixConverter {
  constructor( priority ) {
    this.priority = priority;
    this.operators = Object.keys(priority);
  }
  
  convert(symbols) {
    var exit = [];
    var stack = new Stack(); 
    for (let symbol of symbols) {

      if (this._is_numeric(symbol)) {
        exit.push(symbol);
      } else if (this.operators.includes(symbol)) {
        if(!stack.empty()){
          while(
            this.priority[symbol] < this.priority[stack.peek()]
          ){
            exit.push(stack.pull());
          }
        }
        stack.push(symbol);
      } else if (symbol == '(') {
        stack.push('(');
      } else if (symbol == ')') {
        while(stack.peek() != '(') {
          exit.push(stack.pull());
        }
        stack.pull();
      }

      while(!stack.empty()) {
        exit.push(stack.pull());
      }
    }
    return exit;
  }

  _is_numeric(str) {
    return /^\d+$/.test(str);
  }
}

var converter = new InfixToPostfixConverter( priority );
console.log(converter.convert(Array.from("1+(5+4*3)+3+(1*2+7)+(1*(2+7))")).join(' '))

4.js

var  priority = {
    '-': 1,
    '+': 1,
    '/': 2,
    '*': 2,
    '^': 3
};
var sides = {
    '-': 'l',
    '+': 'l',
    '/': 'l',
    '*': 'l',
    '^': 'p'
}
class InfixToPostfixConverter {
  constructor( priority, sides) {
    this.priority = priority;
    this.sides = sides;
    this.operators = Object.keys(priority);
  }
  
  convert(symbols) {
    var exit = [];
    var stack = new Stack(); 

    for (let symbol of symbols) {

      if (this._is_numeric(symbol)) {
        exit.push(symbol);
      } else  if (this.operators.includes(symbol)) {
        if(!stack.empty()){
          var side = this.sides[symbol];
          while(
            side == "p" && (this.priority[symbol] <= this.priority[stack.peek()]) ||
            side == "l" && (this.priority[symbol] < this.priority[stack.peek()])
          ){
            exit.push(stack.pull());
          }
        }
        stack.push(symbol);
      } else if (symbol == '(') {
        stack.push('(');
      } else if (symbol == ')') {
        while(stack.peek() != '(') {
          exit.push(stack.pull());
        }
        stack.pull();
      }

    }

    while(!stack.empty()) {
      exit.push(stack.pull());
    }
    return exit;
  }

  _is_numeric(str) {
    return /^\d+$/.test(str);
  }
}
let st = new Stack();

var converter = new InfixToPostfixConverter( priority, sides );
console.log(converter);
console.log(converter.convert(Array.from("1+2*3^4*5+6")).join(' '));