Program to toggle all characters in a string

Given a string, the task is to toggle all the characters of the string i.e to convert Upper case to Lower case and vice versa.

Examples:

Input  : gfg
Output : GFG

Input  : aBc12#
Output : AbC12#

Input  : tu@kmiNi
Output : TU@KMInI

Traverse the given string, if uppercase characters come, convert into lowercase and lowercase letter convert into uppercase.

Implementation:

C

// C program to toggle all characters
#include <stdio.h>

void toggleChars(char str[])
{
    for (int i = 0; str[i] != '\0'; i++) {
        if (str[i] >= 'A' && str[i] <= 'Z')
            str[i] = str[i] + 'a' - 'A';
        else if (str[i] >= 'a' && str[i] <= 'z')
            str[i] = str[i] + 'A' - 'a';
    }
}

// Driver code
int main()
{
    char str[] = "GeKf@rGeek$";
    toggleChars(str);
    printf("String after toggle \n");
    printf("%s\n", str);
    return 0;
}

C++

// C++ program to toggle all characters
#include<bits/stdc++.h>
using namespace std;

void toggleChars(char str[])
{
    for (int i=0; str[i]!='\0'; i++)
    {
        if (str[i]>='A' && str[i]<='Z')
            str[i] = str[i] + 'a' - 'A';
        else if (str[i]>='a' && str[i]<='z')
            str[i] = str[i] + 'A' - 'a';
    }
}

// Driver code
int main()
{
    char str[] = "GeKf@rGeek$";
    toggleChars(str);
    cout << "String after toggle " << endl;
    cout << str << endl;
    return 0;
}

Java

// Java program to toggle all characters

class GFG
{

static void toggleChars(char str[])
{
    for (int i=0; i<str.length; i++)
    {
        if (str[i]>='A' && str[i]<='Z')
            str[i] = (char) (str[i] + 'a' - 'A');
        else if (str[i]>='a' && str[i]<='z')
            str[i] = (char) (str[i] + 'A' - 'a');
    }
}

// Driver code
public static void main(String[] args)
{
    char str[] = "GeKf@rGeek$".toCharArray();
    toggleChars(str);
    System.out.println("String after toggle ");
    System.out.println(String.valueOf(str));
}
}

// This code is contributed by 29AjayKumar

Python3

# Python3 program to toggle all characters
def toggleChars(str):

    for i in range(len(str)):
        if (str[i] >= 'A' and str[i] <= 'Z'):
            str = str[:i] + chr(ord(str[i]) + \
                     ord('a') - ord('A')) + str[i + 1:];
        else if (str[i] >= 'a' and str[i] <= 'z'):
            str = str[:i] + chr(ord(str[i]) + \
                     ord('A') - ord('a')) + str[i + 1:];
    return str;

# Driver code
str = "GeKf@rGeek$";
str = toggleChars(str);
print(str);

# This code is contributed by 29AjayKumar

C#

// C# program to toggle all characters
using System;

class GFG
{

static void toggleChars(char []str)
{
    for (int i = 0; i < str.Length; i++)
    {
        if (str[i] >= 'A' && str[i] <= 'Z')
            str[i] = (char) (str[i] + 'a' - 'A');
        else if (str[i] >= 'a' && str[i] <= 'z')
            str[i] = (char) (str[i] + 'A' - 'a');
    }
}

// Driver code
public static void Main(String[] args)
{
    char []str = "GeKf@rGeek$".ToCharArray();
    toggleChars(str);
    Console.WriteLine("String after toggle ");
    Console.WriteLine(String.Join("",str));
}
}

// This code is contributed by Princi Singh

Javascript

<script>

function toggleChars(str)
{
    for (let i = 0; i < str.length; i++)
    {
        if (str[i] >= 'A' && str[i] <= 'Z')
            str[i] =  String.fromCharCode(str[i].charCodeAt(0) + 'a'.charCodeAt(0) - 'A'.charCodeAt(0));
        else if (str[i] >= 'a' && str[i] <= 'z')
            str[i] =  String.fromCharCode(str[i].charCodeAt(0) + 'A'.charCodeAt(0) - 'a'.charCodeAt(0));
    }
}

let str = "GeKf@rGeek$".split("");
toggleChars(str);
document.write("String after toggle ");
document.write((str).join(""));

// This code is contributed by rag2127.
</script>

Output

String after toggle 
gEkF@RgEEK$

Time complexity: O(n), where n is length of string
Auxiliary space: O(1)

We can use the Bitwise XOR operation to toggle all the characters in given string

As we know the ascii value of small and capital char case is differ by just 1 bit (5th bit). We can simply toggle that bit to toggle the char case of a string.

Implementation:

C

// C program to toggle all characters
#include <stdio.h>

void toggleChars(char str[])
{
    for (int i = 0; str[i] != '\0'; i++) {
        if (str[i] >= 65 && str[i] <= 90) {
            str[i] = (char)(str[i] ^ (1 << 5));
        }
    }
}

// Driver code
int main()
{
    char str[] = "GeKf@rGeek$";
    printf("String before toggle\n");
    printf("%s\n", str);
    toggleChars(str);
    printf("String after toggle\n");
    printf("%s\n", str);
    return 0;
}

C++

// C++ program to toggle all characters
#include<bits/stdc++.h>
using namespace std;

void toggleChars(char str[])
{
    for (int i=0; str[i]!='\0'; i++)
    {
        if (isalpha(str[i])) {
          str[i] = (char)(str[i]^(1<<5));
        }
    }
}

// Driver code
int main()
{
    char str[] = "GeKf@rGeek$";
      cout << "String before toggle " << endl;
      cout << str << endl;
    toggleChars(str);
    cout << "String after toggle " << endl;
    cout << str << endl;
    return 0;
}

// This code is contributed by @kaustubhvats08

Java

// Java program to toggle all characters

class GFG
{

static void toggleChars(char str[])
{
    for (int i=0; i<str.length; i++)
    {
        if (Character.isAlphabetic(str[i])) {
            str[i] = (char)(str[i]^(1<<5));
        }
    }
}

// Driver code
public static void main(String[] args)
{
    char str[] = "GeKf@rGeek$".toCharArray();
    System.out.println("String before toggle ");
    System.out.println(String.valueOf(str));
    toggleChars(str);
    System.out.println("String after toggle ");
    System.out.println(String.valueOf(str));
}
}

// This code is contributed by @kaustubhvats08

Python3

# Python3 program to toggle all characters
def toggleChars(s):
    for i in range(len(s)):
      if s[i].isalpha():
        s = s[:i] + str(chr(ord(s[i])^(1<<5))) + s[i+1:]
    return s;

# Driver code
s = "GeKf@rGeek$";
print("String before toggle")
print(s)
s = toggleChars(s);
print("String after toggle")
print(s);

# This code is contributed by @kaustubhvats08

C#

// C# program to toggle all characters
using System;

class GFG
{

static void toggleChars(char []str)
{
    for (int i = 0; i < str.Length; i++)
    {
        if (Char.IsLetter(str[i])){
          str[i] = (char)(str[i]^(1<<5));
        }
    }
}

// Driver code
public static void Main(String[] args)
{
    char []str = "GeKf@rGeek$".ToCharArray();
    Console.WriteLine("String before toggle ");
    Console.WriteLine(String.Join("",str));
    toggleChars(str);
    Console.WriteLine("String after toggle ");
    Console.WriteLine(String.Join("",str));
}
}

// This code is contributed by @kaustubhvats08

Javascript

<script>

function toggleChars(str)
{
    for (let i = 0; i < str.length; i++)
    {
        if ((/[a-zA-Z]/).test(str[i])){
            str[i] = (String.fromCharCode((str[i].charCodeAt(0)^(1<<5))));
        }
    }
}

let str = "GeKf@rGeek$".split("");
document.write("String before toggle ");
document.write((str).join(""));
toggleChars(str);
document.write("String after toggle ");
document.write((str).join(""));

// This code is contributed by @kaustubhvats08.
</script>

Output

String before toggle 
GeKf@rGeek$
String after toggle 
gEkF@RgEEK$

Time complexity: O(n), where n is the length of the string
Auxiliary space: O(1)