Thread: Substring Function

question is :-
int count(String s, char c) that counts how many times the character c occurs inside string s.
You can use the String methods charAt and substring to extract information from string s.

* these methods are required to be fully recursive in that they contain no loops at all;
neither for, while or do-while.*

I guess this a java woreksheet i am doing.
any suggestions/ideas to solve this ?

I tried but i m stuck when i have to get a char out of string(array of char in C)
and to concatenate that in a new string but no such function in c and also i cant use any loops

I have attached the worksheet
recursion.pdf

Recursion is just another way of looping. It's not smallpox, so don't be afraid of it.

Maybe start with just printing out a string of chars, one at a time, using recursion. Sort of, get comfortable with how recursion works.

Instead of posting your assignment, I want you to post your attempt at solving your assignment, and ask very specific questions about what has you stumped, if you should be stumped on anything.

It's up to you to get this work started. Show that you've put work into it, and have a thorough understanding of the assignment.

Originally Posted by quzah

What are you asking? How to do this in Java, or how to do this in C? How about writing it out in words first, then you should be able to do it in either one. The rest is just syntax.


Quzah.

IN C ..yea i have some idea how to do this but cant do in C

This code is working fine..
is it fine ? some errors etc

Code:

#include<stdio.h>
#include<string.h>
#include<stdlib.h>
static int i=-1;;
static int cont=0;
int count(char s[], char c)
{
	i++;
	if(strlen(s)==0)
	{
		return 0;
	}
	if(s[i]==c && i<strlen(s) )
	{
		cont++;
		count(s,c);

	}

		
	if(s[i]!=c && i<strlen(s))
	{
		count(s,c);
	}
	
return cont;
}
int main(void)
{
	char a[]="Hello Tarun Jain Jain aaa Hello HelloH" ;
	int b;
	b=count(a,'H');
	printf("%d\n",b);
	return 0;

}

Is your program working fine?

You should know!

Does it have errors? What are those errors?

You should know, and you should post what those errors are!

For crying out loud.