Tisha Agarwal

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# LeetCode: Count and Say

It's a MEDIUM LEVEL question. At first I found is tough but after going through the question thrice, I understood the concept.

So, before moving on to my question, I just wanna tell that this question can be done using 2 methods-
(1) Recursion (Optimize method)
(2) For-loop

For solving this question, I haven't used recursion. Instead I used `for-loop` method as it helped me in understanding the concept more clearly.

JAVA CODE

``````import java.util.*;
public class Count_and_Say {
public static void main(String[] args) throws Exception
{
Scanner sc=new Scanner(System.in);
System.out.print("Enter the value of n: ");
int n=sc.nextInt();
String s=countAndSay(n);
System.out.println(s);
}
public static String countAndSay(int n) {
String str="1";

for(int i=2;i<=n;i++)
{
StringBuilder temp=new StringBuilder();
char prev=str.charAt(0);
int counter=1;
for(int j=1;j<str.length();j++)
{
char ch=str.charAt(j);
if(ch!=prev)
{
temp.append(counter).append(prev);
prev=ch;
counter=1;
}
else
{
counter++;
}
}
temp.append(counter).append(prev);
str=temp.toString();
}

return str;
}
}
``````