text: #!/usr/bin/env node
  
  'use strict';
  
  const lineReader = require('readline').createInterface(
  {
    input: require('fs').createReadStream(process.argv[2])
  });
  
  lineReader.on('line', (line) =>
  {
    line = line.split(' ').reverse();
  
    let values = [];
  
    line.forEach((token) =>
    {
      if(!isNaN(token))
      {
        values.push(+token);
        return;
      }
  
      let x = values.pop(),
          y = values.pop();
  
      switch(token)
      {
        case '*': values.push(x * y); break;
        case '+': values.push(x + y); break;
        case '/': values.push(x / y); break;
        case '-': values.push(x - y); break;
      }
    });
  
    console.log(Math.trunc(values[0]));
  });
  