https://www.acmicpc.net/problem/2747
import java.util.Scanner
fun main(args: Array<String>){
val sc: Scanner = Scanner(System.`in`)
var n = sc.nextInt()
var f=Array<Int>(n+1,{0})
f[1]=1
for(i in 2..n){
f[i]=f[i-1]+f[i-2]
}
print(f[n])
}