Removing elements between the two zeros

0 0 3 minutes read

Given an integer N which shows the size of the string and in the next line given a string which contains a string of character with only zero and one. The task is to remove a single character each time that comes in between the two zero characters.
During each turn, only one character from the string will be removed that satisfies the following condition :

It must be surrounded by zeroes on both sides.

Examples:

Input : str = “1001
Output : str = “1001”

Input : str = “10101
Output : str = “1001”

Use a loop from 1 to N – 1 and check if any element lies between two zeros such that s[i – 1] = ‘0’ and s[i + 1] = ‘0’. If the condition is satisfied then, delete the character at that position, ad start searching for patterns again.

C++

// C++ program to delete elements between zeros
#include <bits/stdc++.h>
using namespace std;
 
// Function to find the string 
// after operation
string findstring(string s)
{
    int n = s.length();
         
    // Traversing through string 
    for (int i = 1; i < n - 1; i++)
    {
        // Checking for character 
        // Between two zeros
        if ((s.at(i - 1) == '0' && 
            s.at(i + 1) == '0'))
        {
 
            // deleting the character 
            // At specific position
            s.erase(i, 1);
             
            i--;
            if (i > 0 && s.at(i - 1) == '0')
                 i--;
                         
            // updating the length 
            // of the string
            n = s.length();
        }
    }
             
    return s;
}
     
// Drivers code
int main() {
     
    cout << findstring("100100");
    return 0;
}

Java

// Java program to delete elements between zeros
import java.util.*;
 
public class GFG 
{
    // Function to find the string 
    // after operation
    static String findstring(String s)
    {
        int n = s.length();
             
        // use for loop to remove the
        // character between two zeros
        for (int i = 1; i < n - 1; i++)
        { 
            // Checking for character 
            // Between two zeros
            if ((s.charAt(i - 1) == '0' && 
                 s.charAt(i + 1) == '0'))
            {
                     
                // deleting the character 
                // At specific position
                s = s.substring(0, i) + s.substring(i + 1);
                 
                i--;
                if (i > 0 && s.charAt(i - 1) == '0')
                    i--;
                         
                // updating the length 
                // of the string
                n = s.length();
            }
        }
             
        return s;
    }
     
    // Driver code
    public static void main(String[] args)
    {
       String s="100100";
       System.out.println(findstring(s));
    }
}

Python3

# Python3 program to delete elements
# between zeros
 
# Function to find the string
# after operation
def findstring(s):
     
    n = len(s)
    s = list(s)
    i = 1
 
    # Traversing through string
    while i < n - 1:
 
        # Checking for character
        # Between two zeros
        if (s[i - 1] == '0' and
            s[i + 1] == '0'):
 
            # Deleting the character
            # At specific position
            s.pop(i)
 
            i -= 1
            if i > 0 and s[i - 1] == '0':
                i -= 1
 
            # Updating the length
            # of the string
            n = len(s)
        i += 1
 
    return ''.join(s)
 
# Driver code
if __name__ == '__main__':
 
    print (findstring('100100'))
 
# This code is contributed by rutvik_56

C#

// C# program to delete 
// elements between zeros
using System;
 
class GFG
{
    // Function to find the 
    // string after operation
    static string findstring(string s)
    {
        int n = s.Length;
        string st = "";
         
        // Traversing through string 
        for (int i = 1; i < n - 1; i++)
        {
            // Checking for character 
            // Between two zeros
            if ((s[i - 1] == '0' && 
                 s[i + 1] == '0'))
            {
     
                // deleting the character 
                // At specific position
                st = s.Remove(i, 1);
                s = st;
                 
                i--;
                if (i > 0 && 
                    s[i - 1] == '0')
                    i--;
                             
                // updating the length 
                // of the string
                n = s.Length;
            }
        }                 
        return s;
    }
     
    // Driver code
    static void Main()
    {
        Console.Write(findstring("100100"));
    }
}
 
// This code is contributed by 
// Manish Shaw(manishshaw1)

Javascript

<script>
 
// JavaScript program to delete elements
// between zeros
 
// Function to find the string
// after operation
function findstring(s){
     
    let n = s.length
    s = s.split('')
    let i = 1
 
    // Traversing through string
    while(i < n - 1){
 
        // Checking for character
        // Between two zeros
        if (s[i - 1] == '0' && s[i + 1] == '0'){
 
            // Deleting the character
            // At specific position
            s.splice(i,1);
 
            i -= 1
            if(i > 0 && s[i - 1] == '0')
                i -= 1
 
            // Updating the length
            // of the string
            n = s.length
        }
        i += 1
    }
 
    return s.join('')
}
 
// Driver code
 
document.write(findstring('100100'),"</br>")
 
// This code is contributed by shinjanpatra
 
</script>

Output:

Time Complexity: O(N²), where N is the size of the input string and using erase function to delete the value in the string.
Auxiliary Space: O(1)

Feeling lost in the world of random DSA topics, wasting time without progress? It’s time for a change! Join our DSA course, where we’ll guide you on an exciting journey to master DSA efficiently and on schedule.
Ready to dive in? Explore our Free Demo Content and join our DSA course, trusted by over 100,000 zambiatek!