return count of array elements in javascript code example

Example 1: array length javascript

var arr = [10,20,30,40,50]; //An Array is defined with 5 instances

var len= arr.length;  //Now arr.length returns 5.Basically, len=5.
console.log(len); //gives 5
console.log(arr.length); //also gives 5

Example 2: use .map to count length of each element in an array

var lengths = chars.map(function(word){
 return word.length
})

Example 3: use .map to count length of each element in an array

var words = ['Hello', 'world'];

var lengths = words.map(function(word) {
  return word + ' = ' + word.length;
});

console.log(lengths);