JS Exercises

DeepEqual.js

function deepEqual(a, b){
  if (typeof a === 'object' && a !== null && typeof b === 'object' && b !== null){
    	var isEqual = Object.keys(a).length === Object.keys(b).length;
      
      	if (isEqual){
          	for (var key in a){
              isEqual &= b.hasOwnProperty(key);
              
              if (isEqual){
                isEqual &= deepEqual(a[key], b[key]);
              }
              else{
                break;
              }
            }
          
          	return Boolean(isEqual);
        }
    }
  	
  	return a === b;
}

var obj = {here: {is: "an"}, object: 2};
console.log(deepEqual(obj, obj));
// → true
console.log(deepEqual(obj, {here: 1, object: 2}));
// → false
console.log(deepEqual(obj, {here: {is: "an"}, object: 2}));
// → true

ReverseArray.js

function reverseArray(arr){
	var reversed = [];
	
	for (var i = arr.length - 1; i >= 0; i--){
		reversed.push(arr[i]);
	}
	
	return reversed;
}

function reverseArrayInPlace(arr){
	var start = 0, end = Math.floor(arr.length /2);
	
	while (start < end){
		swap(arr, start, arr.length - start - 1);
		
		start++;
	}
	
  return arr;
}

function swap(arr, i, j){
	var temp = arr[i];
	arr[i] = arr[j];
	arr[j] = temp;
}

console.log(reverseArray(["A", "B", "C"]));
// → ["C", "B", "A"];
var arrayValue = [1, 2, 3, 4, 5];
reverseArrayInPlace(arrayValue);
console.log(arrayValue);
// → [5, 4, 3, 2, 1]

Sum_Range.js

//1. Create an array from a range [start, end] with step increment. If step is not defined, it will be 1. 
//Accept also negative step but the range needs to start from large to small number.
//2. Calculate sum of elements of given array

function sum (arr){
	var result = 0;
  for (var i = 0; i < arr.length; i++){
  	result += arr[i];
  }
  return result;
}

function range(start, end, step){
  	var arr = [];
  		step = step ? step : 1;
  
  	if ((start > end && step <= 0) || (start <= end && step > 0)){      
      var begin = (start > end) ? end : start,
      	stop = (start > end) ? start : end;
      
  		var increment = Math.abs(step);
      
      for (var i = begin; i <= stop; i+=increment){
      	if (start > end){
        	arr.unshift(i);
        }
        else{
          	arr.push(i);
        }
      }
    }
  
  	return arr;
}
console.log(range(1, 10));
// → [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
console.log(range(5, 2, -1));
// → [5, 4, 3, 2]
console.log(sum(range(1, 10)));
// → 55

console.log(range(5,2,1));

console.log(range(5,2));