정수!
형식으로 나타내며 1부터 정수까지의 숫자를 모두 곱한 값을 의미
예를 들어 5!
은
5 x 4 x 3 x 2 x 1 = (5-0) x (5-1) x 5-2 x 5-3 x 5-4 = 120이다.
이걸 코드로 나타내보자
<script>
const input = require('fs').readFileSync('/dev/stdin').toString().trim();
function factorial (num) {
let result = 1;
if (num === 0 || num === 1) {
return 1;
}
for (let i = 0; i < num; i++) {
result *= (num - i);
}
return result;
}
console.log(factorial(input));
</script>
<script>
(function () {
const input = require('fs').readFileSync('/dev/stdin').toString().trim();
const N = input[0];
function factorial (num) {
let result = 1;
if (num === 0 || num === 1) {
return 1;
}
for (let i = 0; i < N; i++) {
result *= (num - i);
}
return result;
}
console.log(factorial(N));
})();
</script>
<script>
const input = require('fs').readFileSync('/dev/stdin').toString().trim();
function factorial (num) {
if (num === 0 || num === 1) {
return 1;
}
return num * factorial(num-1);
}
console.log(factorial(input));
</script>
<script>
function(){
const input = require('fs').readFileSync('/dev/stdin').toString().trim();
function factorial (num) {
if (num === 0 || num === 1) {
return 1;
}
return num * factorial(num-1);
}
console.log(factorial(input));
})();
</script>