Problem solving-2

//Difference between maximum and minimum number
// sorting
//count occurrence
// factorial and recursion

//must use rest operator to receive the parameters

// function differMaxMin(...numArr) {
//solution-1 simple loop
// let max_num = numArr[0]
// let min_num = numArr[0]
// for (let i = 0; i < numArr.length; i++) {
//   if (numArr[i] > max_num) {
//     max_num = numArr[i]
//   }
//   if (numArr[i] < min_num) {
//     min_num = numArr[i]
//   }
// }
// console.log(max_num - min_num)
//Math.max, Math.min
// const result = Math.max(...numArr) - Math.min(...numArr)
// const result = Math.max.apply(null, numArr) - Math.min.apply(null, numArr)
//console.log(result)
//reduce
//solution-3
// const result1 = numArr.reduce((a, b) => {
//   return a > b ? a: b
// })
// const result2 = numArr.reduce((a, b) => {
//   return a < b ? a : b
// })
// console.log(result1- result2)
//solution-4 (sort)
// const sortedArr = numArr.sort((a, b) => a - b)
// const max_num = sortedArr[sortedArr.length - 1]
// const min_num = sortedArr[0]
// console.log(max_num - min_num)
// }

// b-a (decending)

// a - b (ascending)
// 4 - 2 = 2
// 2, 4 ,
// 2, 4

// differMaxMin(10, 2, 3, 4) //4-1 = 3

//factorial and recursion 4! = 4 * 3 * 2 * 1

// 4 * (4 - 1) * (3 - 1) * (2 - 1) * 1

//recursion (calling itself)

// 4 * 3 * 2 * 1 = 24

// function factorial(number) {
// if (number <= 1) {
//   return 1
// }
//solution-2
// return number * factorial(number - 1)
//return result(factorial)
//solution - 1 (simple loop)
// let result = 1
// for(let i = 1; i <= number; i++ ){
//   console.log(result, i)
//   result *= i
// }
// for (let i = number; i > 0; i--) {
//   console.log(result, i)
//   result
//   result *= i
// }
// console.log(result)
// }

// console.log(factorial(24))

function countOccurrence(numArr) {
  //solution -1 (plain way)
  //  const obj = {}
  //  for(let num of numArr){
  //    if(num in obj){
  //      obj[num]++
  //    }else{
  //      obj[num] = 1
  //    }
  //    console.log(num)
  //  }
  //  console.log(obj)
  //solution-2(Reduce)
  // return numArr.reduce((obj, currentNum) => {
  //   obj[currentNum] ? obj[currentNum]++ : (obj[currentNum] = 1)
  //   return obj
  // }, {})
}

// console.log(countOccurrence([1, 1, 2, 2, 3, 5]))

// hash map (hashing){
//  '1': 2,
//  '2': 2,
//  '3' : 1,
//  '5': 1
// }