Recursively remove all adjacent duplicates

Implementation

#include <iostream>
#include <string.h>
using namespace std;

char* removeHelper(char *str, char *last_char){
     
    if (str[0] == '\0' || str[1] == '\0')
        return str;


    if (str[0] == str[1]){
        *last_char = str[0];
        while (str[1] && str[0] == str[1])
            str++;
        str++;
        return removeHelper(str, last_char);
    }
    char* newStr = removeHelper(str+1,last_char);
    if (newStr[0] && newStr[0] == str[0]){
        *last_char = str[0];
        return (newStr+1);
    }

    if (newStr[0] == '\0' && *last_char == str[0])
        return newStr;
    newStr--;
    newStr[0] = str[0];
    return newStr;
}
 
char *remove(char *str){
    char last_char = '\0';
    return removeHelper(str, &last_char);
}
 
int main(){
    char str[] = "acbbcddf";
    cout << remove(str) << endl;
    return 0;
}

You can also try this code with Online C++ Compiler

Run Code

Output

af

You can try by yourself with the help of online C++ Compiler.

Also read -  Decimal to Binary c++

Frequently Asked Questions

What are adjacent duplicates in a string?

Two adjacent characters in a string are adjacent duplicate characters if they are the same.

How do I recursively remove adjacent duplicates from a string?

To recursively remove adjacent duplicates, compare consecutive characters in the string. If duplicates are found, remove them and recursively call the function on the new string. Repeat this process until no adjacent duplicates remain, returning the final output.

How do you remove all duplicates from a string solution?

To remove all duplicates from a string, identify the unique characters by processing each character only once. Then, combine these unique characters into a new string, ensuring that each character appears only once in the final output.

Conclusion

In this blog, we learned the concept of the C++ programming language using which we could code how to recursively remove all adjacent duplicate characters in a string. We hope that this blog has helped you enhance your knowledge, and if you wish to learn more, check out Code360.