View Code of Problem 23

#include<stdio.h>
int main()
{
	int M;
	long int a[90];
	a[1]=1;
	a[2]=2;
	while(scanf("%d",&M)!=EOF)
	{	
		if(M==0)break;
		else
		{
			if(M==1)printf("1\n");	
			else if(M==2)printf("2\n");
			else
			{
				for(int i=3;i<=M;i++)
				{
					a[i]=a[i-1]+a[i-2];
				}
				printf("%ld\n",a[M]);
			}		
		}		
	}
	return 0;
}