function recursion and iteration

Recursive defect: When the stack process is executed more often, the computational amount is too large. But each tail recursion can be written as a loop (using a non-native word is iterative)

The FABONACII sequence is implemented in an iterative way:

#include <stdio.h>int fibonacii (int n) {    int temp = 0;    int a = 1;//Remember to assign the first two numbers the initial value    int b = 1;    if (n <= 2)        return 1;    while (n > 2)    {        temp = a + b;        A = b;        b = temp;//avoid written a = temp; b = A; At this point a has changed!=1 and then the assignment to B has no meaning        n--;//adjust the value stored in AB to move forward    }    return temp; int main () {    printf ("%d\n", Fibonacii (6));    return 0;}

To implement factorial in an iterative way:

#include <stdio.h>int fac (int n) {    int ret = 1;    while (n)    {        ret = ret * N;        n--;//ret = 1*n,ret = N (n-1) .... Return back to    ret;} int main () {    printf ("%d\n", FAC (3));    return 0;}

function recursion and iteration