3 Ways for Traversal of Strings

String Traversal operations refers to process of one character at a time. Often we start at the beginning, select each character in turn, do something to it, and continue until the end.

Examples:

Input: str = “GeeksforGeeks”
Output: G e e k s f o r G e e k s

Input: str = “Coder”
Output: C o d e r

Method 1: Using For Loops

• Initialize a variable with the string you want to traverse.
• Use a for loop to iterate over each character in the string.
• In each iteration, the loop variable holds the current character.
• You can print or process the character within the loop.

For Example:

// C++
#include <iostream>
#include <string>

int main() {
    std::string text = "Hello,World!";

    for (char c : text) {
        std::cout << c << std::endl;
    }

    return 0;
}

// C
#include <stdio.h>
#include <string.h>

int main() {
    char text[] = "Hello, World!";
    int len = strlen(text);

    for (int i = 0; i < len; i++) {
        printf("%c\n", text[i]);
    }

    return 0;
}

// Java
public class StringTraversal {
    public static void main(String[] args) {
        String text = "Hello, World!";

        for (int i = 0; i < text.length(); i++) {
            System.out.println(text.charAt(i));
        }
    }
}

# Python
text = "Hello, World!"

for char in text:
    print(char)

// C# 
using System;

public class StringTraversal
{
    public static void Main(string[] args)
    {
        string text = "Hello, World!";

        for (int i = 0; i < text.Length; i++)
        {
            Console.WriteLine(text[i]);
        }
    }
}

// This code is contributed by Tapesh(tapeshdua420)

// JavaScript
const text = "Hello, World!";

for (let i = 0; i < text.length; i++) {
    console.log(text[i]);
}

H
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W
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!

Method 2: Using a While Loop

• Initialize a variable with the string you want to traverse.
• Initialize an index variable (e.g., index) to 0.
• Use a while loop that continues as long as the index is less than the length of the string.
• Within the loop, access the character at the current index and process it.
• Increment the index after processing the character to move to the next character.

For Example:

// C++
#include <iostream>
#include <string>

int main() {
    std::string text = "Hello, World!";
    int index = 0;

    while (index < text.length()) {
        std::cout << text[index] << std::endl;
        index++;
    }

    return 0;
}

// C
#include <stdio.h>
#include <string.h>

int main() {
    char text[] = "Hello, World!";
    int len = strlen(text);
    int index = 0;

    while (index < len) {
        printf("%c\n", text[index]);
        index++;
    }

    return 0;
}

// Java
public class StringTraversal {
    public static void main(String[] args) {
        String text = "Hello, World!";
        int index = 0;

        while (index < text.length()) {
            System.out.println(text.charAt(index));
            index++;
        }
    }
}

# Python
text = "Hello, World!"
index = 0

while index < len(text):
    print(text[index])
    index += 1

// C# Implementation
using System;

public class StringTraversal
{
    public static void Main(string[] args)
    {
        string text = "Hello, World!";
        int index = 0;

        while (index < text.Length)
        {
            Console.WriteLine(text[index]);
            index++;
        }
    }
}

// This code is contributed by Tapesh(tapeshdua420)

// JavaScript
const text = "Hello, World!";
let index = 0;

while (index < text.length) {
    console.log(text[index]);
    index++;
}

H
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W
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!

Method 3: Using forEach (JavaScript Specific for Arrays)

• This method is specific to JavaScript and is used when you have an array of characters created from a string.
• Create an array from the string, where each element of the array represents a character.
• Use the forEach method on the array to iterate over each character.
• In each iteration, the loop function receives the current character as an argument.
• You can print or process the character within the loop.

For Example:

// JavaScript (for an array of characters)
const text = "Hello, World!";
const chars = text.split('');

chars.forEach(function(char) {
    console.log(char);
});

H
e
l
l
o
,
 
W
o
r
l
d
!