Question

Code programs using ReadlineSync for prompts.

Note: For all programs, create and call a main function, and if required additional functions called by the main. Also please use the ES6 style of keywords => instead of the older function and for local scope variables use the keyword let, not var

Name: coinflip.js

For this program you will have two functions, one called main and the second called flip. This program is also required the use of a loop construct.

Write a program that simulates tossing a coin. Prompt the user for how many times to toss the coin. Code a function called flip with no parameters that randomly ( use the math library random ) returns either the String "heads"or the string "tails". Call this function in main as many times as requested using a loop and report the results. See Example outputs below.

Example Outputs

How many times should I toss the coin? 1000
Results of 1000 tosses.
Heads: 483, tails: 517

How many times should I toss the coin? 1000000
Results of 1000000 tosses.
Heads: 500074, tails: 499926
Recheck the requirements before you submit.

Answer 1

//import the readline library for standard input from console

const readline = require("readline").createInterface({

  input: process.stdin,

  output: process.stdout

});

//flip function that returns 'heads' or 'tails'

let flip = () => {

  //if the result is 0 return heads

  if (Math.floor(Math.random() * 2) == 0) {

    return "heads";

  }

  //else return tails

  else {

    return "tails";

  }

};

//main function

let main = () => {

  let mapper = { heads: 0, tails: 0 };

  // prompt the user for number of flips

  readline.question("How many times should I toss the coin?", n => {

    //Iterate for the number opf times

    for (let i = 0; i < n; i++) {

      //call flip() to get the result

      result = flip();

      // increase the count of the mapper

      mapper[result]++;

    }

    // log the output

    console.log(`Result of ${n} tosses.`);

    console.log(`Heads: ${mapper["heads"]}, Tails: ${mapper["tails"]}`);

    //close the stream

    readline.close();

  });

};

//call the main function

main();