const target = 'snippetzone'.split``;

const leng = target.length;

const alphabet = 'abcdefghijklmnopqrstuvwxyz'.split``;

function randomString() {

  let str = [];

  for (let i = 0; i < leng; i++) {

    str.push(randomChar());

  }

  return str;

}

function randomChar() {

  return alphabet[Math.floor(Math.random() * alphabet.length)];

}

let iterations = 0;

const search = randomString();

const indices = [];

for (var i = 0; i < leng; i++) indices.push(i);

let found = false;

function loop() {

  for (let i = 0; i < 10; i++) {

    if (indices.length > 0) {

      let ii = Math.floor(Math.random() * indices.length);

      let index = indices[ii];

      search[index] = randomChar();

      if (search[index] == target[index]) {

        indices.splice(ii, 1);

      }

      console.log(search.join(','));

      iterations++;

    } else {

      console.log('found after', iterations, 'iterations');

      found = true;

      break;

    }

  }

  if (!found) {

    requestAnimationFrame(loop);

  }

}

loop();