#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <time.h>
#include "bignums.h"

#if 0
#define NUM1_SIZE 15
#define NUM2_SIZE 15

static inline char 
randchar() {
	return (rand() % 9) + '0';
}
#endif

static char *
fibonacci(unsigned long long term) {
	char *prev1, *prev2, *res;
	
	prev2 = malloc(2);
	assert(prev2);
	strcpy(prev2, "0");
	
	if(term < 3) {
		if(term == 1 || term == 2)
			strcpy(prev2, "1");
		}
		return prev2;
	} 
	
	term--;
	
	prev1 = malloc(2);
	assert(prev1);
	strcpy(prev1, "1");
	
	while(term--) {
		res = add(prev1, strlen(prev1), prev2, strlen(prev2));
		free(prev2);
		prev2 = prev1;
		prev1 = res;
	}
	free(prev2);
	return res;
}

int main(int argc, char *argv[]) {
	char *result;
#if 0
	char num1[NUM1_SIZE+1], num2[NUM2_SIZE+1], *result;
	int i;
	srand(time(NULL));

	for(i = 0; i < NUM1_SIZE; i++)
		num1[i] = randchar();
	num1[NUM1_SIZE] = '\0';
	for(i = 0; i < NUM2_SIZE; i++)
		num2[i] = randchar();
	num2[NUM2_SIZE] = '\0';
	
	printf("\t%s\n", num1);
	printf("+\t%s\n", num2);
	printf("=\n");
	result = add(num1, NUM1_SIZE, num2, NUM2_SIZE);
	printf("\t%s\n", result);
	free(result);
#endif
	if(argc >= 2) {
		result = fibonacci(atoll(argv[1]));
		printf("%s\n", result);
		free(result);
	} else {
		printf("%s <term>\n", argv[0]);
	}
	return 0;
}