Javascript - 팩토리얼, 팰린드롬

 

// 팩토리얼
// 0! = 1
// 1! = 1
// 2! = 1 * 2 = 2
// 3! = 1 * 2 * 3 = 6
// 4! = 1 * 2 * 3 * 4 = 24
// 5! = 1 * 2 * 3 * 4 * 5 = 120
// 6! = 1 * 2 * 3 * 4 * 5 * 6 = 720
// n! = 1 * 2 * 3 * ... * (n-1) * n =

function factorial(n) {
  let result = 1;
	
  for(let i = 1 ; i <= n ; i++) {
    result = result * i
  }
  return result;
}

console.log(factorial(12));  // 479001600
console.log(factorial(6));   // 720
console.log(factorial(3));   // 6
console.log(factorial(0));   // 1

---

// 팰린드롬
function isPalindrome(word) {

let reverse_word = ""
for(let i = word.length - 1 ; i >=0 ; i--){
  reverse_word = reverse_word + word[i]
}
if(word === reverse_word) {
  return true
} else {
  return false
}
}

console.log(isPalindrome("racecar"));
console.log(isPalindrome("stars"));
console.log(isPalindrome("기러기"));
console.log(isPalindrome("123321"));
console.log(isPalindrome("hello"));
console.log(isPalindrome("kayak"));