Remove three consecutive duplicates from string

// Java program to remove three consecutive
// duplicates
import java.util.*;

class GFG 
{

// function to remove three consecutive
// duplicates
static void remove3ConsecutiveDuplicates(String str)
{
    Vector<Character> v = new Vector<>();
    for (int i = 0; i < str.length(); ++i) 
    {
        v.add(str.charAt(i));

        if (v.size() > 2) 
        {
            int sz = v.size();

            // removing three consecutive duplicates
            if (v.get(sz - 1) == v.get(sz - 2) && 
                v.get(sz - 2) == v.get(sz - 3)) 
            {
                v.setSize(sz - 3); // Removing three characters
                                // from the string
            }
        }
    }

    // printing the string final string
    for (int i = 0; i < v.size(); ++i)
        System.out.print(v.get(i));
}

// Driver code
public static void main(String[] args) 
{
    String str = "aabbbaccddddc";
    remove3ConsecutiveDuplicates(str);
}
}

// This code contributed by Rajput-Ji

import java.util.regex.*;

public class GFG {
    // Function to remove consecutive duplicates from a
    // string
    static String
    removeConsecutiveDuplicates(String inputStr)
    {
        // Regular expression pattern to match consecutive
        // duplicate characters
        Pattern pattern = Pattern.compile("(\\w)\\1{2}");

        // Find the first match of the pattern in the input
        // string
        Matcher match = pattern.matcher(inputStr);
        boolean found = match.find();

        // While there are consecutive duplicates found,
        // remove them from the string
        while (found) {
            inputStr = inputStr.replaceAll(
                pattern.pattern(), "");
            match = pattern.matcher(inputStr);
            found = match.find();
        }

        return inputStr;
    }

    public static void main(String[] args)
    {
        String inputStr = "aabbbaccddddc";
        String result
            = removeConsecutiveDuplicates(inputStr);
        System.out.println(result);
    }
}

/*package whatever //do not write package name here */

class GFG {
    public static String removeConsecutiveDuplicates(String str)
    {
        int n = str.length();

        // Create a dynamic programming table to track the
        // counts of consecutive duplicates
        int[] dp = new int[n];
        dp[0] = 1;

        StringBuilder sb = new StringBuilder();
        sb.append(str.charAt(0));

        for (int i = 1; i < n; i++) {
            // If the current character is the same as the
            // previous one, increment the count in the
            // dynamic programming table
            if (str.charAt(i) == str.charAt(i - 1)) {
                dp[i] = dp[i - 1] + 1;
            }
            else {
                dp[i] = 1;
            }

            // Append the current character to the result
            // string
            sb.append(str.charAt(i));

            // If the count reaches three, remove the last
            // three characters
            if (dp[i] == 3) {
                sb.delete(sb.length() - 3, sb.length());
            }
        }

        return sb.toString();
    }

    public static void main(String[] args)
    {
        String str1 = "aabbbaccddddc";
        String result1 = removeConsecutiveDuplicates(str1);
      
        System.out.println("Input: " + str1);
        System.out.println("Output: " + result1);

        String str2 = "aabbaccddc";
        String result2 = removeConsecutiveDuplicates(str2);
        System.out.println("Input: " + str2);
        System.out.println("Output: " + result2);
    }
}
//This code is contributed by Silu