fib3.c

来自「稀疏矩阵、链表、图、队列、二叉树、多叉树、排序、遗传算法等的实现」· C语言 代码 · 共 36 行

#include <stdlib.h>
#include <stdio.h>

static unsigned long count;

int
fib(int x) {
	int i, a[3];

	if (x < 3)
		return 1;

	a[1] = a[0] = 1;
	for (i = 2; i < x; ++i) {
		a[2] = a[0] + a[1];
		a[0] = a[1];
		a[1] = a[2];
	}

	return a[2];
}

int
main(void) {
	int i, f;

	for (i = 1; i < 20; ++i) {
		count = 0;
		f = fib(i);
		printf("fib(%02d) gives %d after %lu iteration%s.\n",
			i, f, count, count == 1 ? "" : "s");
	}

	return 0;
}