View Code of Problem 23

#include <iostream>
using namespace std;
int main(){
	int n,a[100];
	a[1]=1;a[2]=2;
	for(int i=3;i<=90;i++)
		a[i]=a[i-1]+a[i-2];
	while(cin>>n){
		if(n==0)
			break;
		cout<<a[n]<<endl;
	}
	return 0;
}