C-(函数)斐波那契数

#define _CRT_SECURE_NO_WARNINGS 1

#include<stdio.h>//采用递归求n的阶乘
int count = 0;
//递归可以求解 但是效率太低
int Fib(int n)
{
    //统计第三个斐波那契数的计算机次数
    if (n == 3)
        count++;

    if (n <= 2)
        return 1;
    else
        return Fib(n - 1) + Fib(n - 2);
}
int main()
{
    int n = 0;
    scanf("%d", &n);
    int ret = Fib(n);

    printf("%d\n", ret);

    return 0;
}

#define _CRT_SECURE_NO_WARNINGS 1

#include<stdio.h>

int Fib(int n)  //斐波那契数 循环
{
    int a = 1;
    int b = 1;
    int c = 1;
    while (n > 2)
    {
        c = a + b;
        a = b;
        b = c;
        n--;
    }
    return c;
}
int main()
{
    int n = 0;
    scanf("%d", &n);
    int ret = Fib(n);

    printf("%d\n", ret);

    return 0;
}