[recursion] Forum Topics

i have a c code for printing all permutation of string. I have a problem in understanding ,how recursion work in for loop and how backtracking is used in this code. Another question is that how stack work in recursion under for loop. my code--> # include <stdio.h> void swap …

def isPrime(num,div=2): if(num==div): return True elif(num % div == 0): return False else: return isPrime(num,div+1)

In most modern languages, there are two fundamental approaches to repeating an action: either *iteration*, in which an action is placed inside a special-purpose structure which causes the action to be repeated, or *recursion*, in which a general-purpose function calls itself (or another function which in turn calls the earlier …

Hey everyone, I really need help in solving a problem that I have to use recursion for. I have a list of paper objects. Each paper object has its own author(s) objects. Each author object knows which paper(s) objects they belong to. I have to build a scholarly neighborhood for …

This is just a piece of code I've found over the Internet, and I'm trying to understand why the output is 3 1 1 2 1 1 2 3. Could anyone explain using a stack representation or something else, I am really stuck on this one. #include <iostream> using namespace …

#include <iostream> using namespace std; int f(int i) { if(i == 1) { return (1); } else { return 2*f(i-1); } } int main() { cout << f(5) << endl; //<--- I don't understand why this is 16. return 0; } I am having trouble understanding why f(5) = 16 …

Hi. I was wondering how I could replace objects in a list without using a single loop. Here's what I have in terms of algorithm; but, I don't know how to implement.: replace(List list, oldObject, newObject) 1. if the first element in list is not null 2 if the old …

Hey guys I had an assignment to recursively write the Towers of Hanoi then test it. I did not have too much of an issue getting the program written But I am not sure what the book means by test the efficiency do they want the number of moves my …

float det(float A[][10],int m) { float B[10][10],d=0; int i,a,b,x,y; if(m==2) return (A[0][0]*A[1][1])-(A[1][0]*A[0][1]); else { x=0;y=0; for(i=0;i<m;i++) { for(a=0;a<m;a++) { if(a==i) continue; else { for(b=1;b<m;b++) { B[x][x]=A[a][b]; x++; } } } if(i%2) d-=det(B,x); else d+=det(B,x); } } return d; } I tried to run the program, but it exits with error …

Let's use the basic example.. I have a table for tree representation with just 3 columns: ID, PARENT_ID,NAME. If I delete a record X, how can I delete all recursive records that refer as PARENT_ID of deleted record?

Im trying to add Total function and isMono functions to this code. Did total already Need help with function ismono which returns whether a tree is mono (all the elements are unique aka no element appears more than one time) or not. Please this is the original program #ifndef T_H …

Hello, First of all some background. My friend and I are having a bit of a competition over theoretically infinite number storage. We have agreed that the first person with a working arbitrary precision integer library with the theoretical ability to store an infinitely large number (IE: if the hard …

# This is an advanced guess the number game. import random # The very basis of this game. import math # Used for math.ceil import time # Used to split up long portions of text. def errorDisplay(errorCode): if errorCode == '1': print('\n\n\nError ' + errorCode + ': unlockedGameModes outside of …

I am trying to write several different sorting algorithms in order to time the differences between them when reading a file of a half million integers. For testing purposes, I am only using a few hundred integers, but I am getting a stack overflow error. Also, for testing reasons, I …

Hello all, I'm having trouble writing a spell checker as my recursive function isn't returning what I would like it to. It is meant to chop off the ends of words likes "baker" to bake and check against a predined dictionary. I used recursion for words like "baker's". I have …

Hello all, I am trying to get a bunch of sub-keys and values from the registry in vb 2010 and i remember in vb6 this was quite easy. Can anyone share code to help? Or a link where I can go? I've been searching for nearly 8 hours on line …

i am trying to use recursion to find the occurence of a specific character in an array of characters public class CharacterCounter { public static void main(String [] args) { char test[] = {'a', 'b', 'a', 'c', 'd', 'a', 'e', 'a', 'f', 'g', 'h', 'a', 'i', 'a'}; char searchChar = …

Hello, Would someone be willing to take a look at this segment of code? I am trying to figure out how this segment of code operates. I can see how the program can evaluate a simple prefix statement like + 7 6. I cannot see how the program can solve …

Hi everyone I am having trouble finding the nth node of a binary search tree in an inorder traversal. I am getting NullPointerExceptions for any numbers other than 2 and 3 and even those print out the wrong values. If anyone could help it would be greatly appreciated. The method …

Hi I'm working on the implementation of a boolean method to check if an expression has balanced parentheses using recursion. I cant figure out how to check if two elements of a given expression match i.e ( ). I was able to finish it without a problem using stacks, but …

I inherited a website here at work. The menu system uses a convoluted jquery / javascript structure. There are 8 different types of "users" for this website, from administrator to contractor or accountant, etc, and the person made 8 different versions of the menus covering nearly 80 different pages within …

Hi again, I have the simple code below, and I receive the error "best overloaded method match has some invalid arguments". I tried to return a string or an int and then it said that I can't implicitly convert void to string. Any ideas on how I can overcome it? …

Hi guys, I have this code - I am trying to find if a number is present in a given array using recursion. The thing is, I get the error "not all code paths return a value". I don't know how to fix this. Please advise. using System; namespace checkArrayForValue …

this code gives the correct result upto size 6 (i'v run this a few times, and 6 seems to be the boundary), although the intermediate steps are all insane! then onwards, from size 7, it returns minimum value 0 /*minimum of an array using recursion*/ #include<stdio.h> #include<stdlib.h> int findMin(int* arr,int …

Is it possible to convert a postfix expression to prefix expression using only recursion? If possible what's the algorithm?

Hello, Does anyone know how to write recursive SQL statement for hierarhic output places from next table: TABLE PLACES: id-----place----------idParentPlace 1......World..........Null 2......Europe.........1 3......Mediterranean..2 4......North Europe...2 5......Italy..........3 6......Greece.........3 7......Island.........4 8......Norway.........4 I don't know if this is totally correct SQL recursive statement: WITH recursion AS (SELECT id, place, idParentPlace, 1 AS hierarhic …

Hello guys, Do anyone know how to write recursive SQL statement for hierarhic output places from next table: id-----place----------idParentPlace 1......World..........Null 2......Europe.........1 3......Mediterranean..2 4......North Europe...2 5......Italy..........3 6......Greece.........3 7......Island.........4 8......Norway.........4 I was looking for alot of tutorials but didn't find anything useful. Any help is the most welcome! Regards, TP

public static void nonRecursiveInorder(Node node) { Stack<Node> st=new Stack(); st.push(node); Node temp; while(!st.isEmpty()) { temp=st.peek(); if(temp.left!=null && temp.left.visited==false) st.push(temp.left); else { if(temp.left==null && temp.right!=null && temp.right.visited==false) { System.out.print(" "+temp.value); temp.visited=true; st.pop(); st.push(temp.right); } else { if(temp.left!=null && temp.left.visited==true && temp.right!=null && temp.right.visited==false) { System.out.print(" "+temp.value); temp.visited=true; st.pop(); st.push(temp.right); } else …

Hi How can I create a recursive method that counts how many files with a certain file extension, which is in a directory and the directory's sub directories. Exceptions that can be thrown in the search of the file tree should be handled appropriately. The user of the program should …