View Code of Problem 23

#include<stdio.h>
#include<math.h>
#include<string.h>  
int main(){ 
    long int a[90];
    int i,x;
    a[0]=1;
    a[1]=2;
    for(i=2;i<90;i++)
    a[i]=a[i-1]+a[i-2];
    while(scanf("%d",&x)!=EOF){
    	if(x==0) break;
    	printf("%ld\n",a[x-1]); 
	}
    
	return 0;
}