How recursive function control flow change for static variable?

» cpp » How recursive function control flow change for static variable?

By : froncthetonc

Date : November 18 2020, 04:01 AM

With these it helps The series of 6s is printed because of the second printf in recurse().
By the time the recursive calls are complete the value of c has already been incremented upto 6. So it will print 6 five times.

code :

void recurse()
{
    static int c = 1; int d;

    if(c > 5) {
        d = d - 1;
         return ;
    }
    printf("Count = %d\n",c);
    d = c;
    c = c + 1;
    recurse();
    printf("Count = %d\n",d);
}

Share :

Why doesn't the recursive function call not change the execution flow?

By : Oriana Gutierrez

Date : March 29 2020, 07:55 AM

I wish this helpful for you You've got a bunch of problems here. Here's a version that actually works:

code :

use strict;
use warnings;

sub dir_list1
{
    my $path = $_[0];
    for (<$path/*>) {
        if (-f $_) {
            print "$_\n";
        }
        else {
            print "enter dir: $_\n";
            dir_list1($_);
            print "leave dir: $_\n";
        }
    }
}
dir_list1(".");

Understanding control flow of recursive function that uses splicing

By : vivekkharb26

Date : March 29 2020, 07:55 AM

should help you out It may make more sense if you actually write out the calls and then what's returned from each of those calls. Starting from the uppermost reverse("hello") (sorry -- shortened reverse_string for my lazy typing):

code :

1: return reverse('ello') + 'h'
2:    return reverse('llo') + 'e'
3:       return reverse('lo') + 'l'
4:          return reverse('o') + 'l' 
5:             return 'o'

'o' is returned from 5
'ol' is returned from 4
'oll' is returned from 3
'olle' is returned from 2
'olleh' is returned from 1

Javascript: initializing a variable once (like a static variable) in a recursive function

By : Raphael Barbosa

Date : March 29 2020, 07:55 AM

this will help I have a recursive function, which returns the leaf nodes of a tree (which is in the form of nested objects): , You can use an inner function:

code :

function retrieve(a) {
  var names = [];
  function _retrieve(a) {
    if (a.left != null)
      _retrieve (a.left)
    if (a.right != null)
      _retrieve (a.right)
    if (a.left == null && a.right == null)
      names.push(a)
   }
   _retrieve(a);
   return names;
}

Replace global variable with static variable in recursive function

By : Kalel

Date : March 29 2020, 07:55 AM

it fixes the issue You make the function return the updated counter, so you don't have to maintain it globally; see *** comments:

code :

let primes = [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97]

function findPrime(arr, target, counter) {             // ***
  if (typeof counter === "undefined") {                // ***
    counter = 1;                                       // ***
  }                                                    // ***

  let guess = arr[Math.floor(arr.length / 2)]

  if (guess > target) {

    arr = arr.splice(0, arr.length / 2)
    return findPrime(arr, target, counter + 1)         // ***

  } else if (guess < target) {

    arr = arr.slice(arr.length / 2)
    return findPrime(arr, target, counter + 1)         // ***

  } else {

    console.log('guesses taken: ' + counter)
    console.log('target is: ' + guess)
    return counter;
  }
}


findPrime(primes, 2)

How does the control flow with these multiple calls to a recursive function?

By : Khouloud

Date : March 29 2020, 07:55 AM

this will help There are multiple possibilities to explore the control flow (as long as there is no multithreading or multiprocessing which isn't in this case).
One option would be to execute your sample code step by step in a debugger. Another option could be "printf" debugging. For this, I added some printf()s to your orignal code: