String Programs

A String is a collection of characters stored together to represent text in a program.

These characters can be letters, numbers, symbols, or spaces.
String is immutable

Example:

"Priya"
"Hello World"
"12345"
"Java@2026"

All of these are strings because they store text inside quotes.
Accessing the First Character of a String
Python

name = "priya"
print(name[0])

In JavaScript

const name = "priya"

console.log(name[0])

Accessing the middle Character of a String
Python

name = "priya"

# Find the middle index
middle_index = len(name) // 2

# Print the middle character
print(name[middle_index])

JavaScript

const name = "priya";

// Find the middle index
const middleIndex = Math.floor(name.length / 2);

// Print the middle character
console.log(name[middleIndex]);

Accessing the last Character of a String
Python

name = "priya"
print(name[-1])

JavaScript

const name = "priya";

// Get the last character
console.log(name[name.length - 1]);  // Output: "a"

capitalize the first letter of a string
In Python

name = "priya"

# Capitalize only the first letter
result = name[0].upper() + name[1:]

print(result)

In JavaScript

let name = "priya";

// Capitalize only the first letter
let result = name[0].toUpperCase() + name.slice(1);

console.log(result);

Java

Changing Case of Specific Characters in a String
In Python

name = "priya"
length = len(name)

result = (
    name[0].upper() +                       # First character uppercase
    name[1:length // 2] +                    # Characters from 1 to middle-1 unchanged
    name[length // 2].upper() +              # Middle character uppercase
    name[length // 2 + 1:length - 1] +       # Characters after middle to second last unchanged
    name[length - 1].upper()                 # Last character uppercase
)

print(result)

In JavaScript

let name = "priya";
let len = name.length;

let result =
    name[0].toUpperCase() +
    name.substring(1, Math.floor(len / 2)) +
    name[Math.floor(len / 2)].toUpperCase() +
    name.substring(Math.floor(len / 2) + 1, len - 1) +
    name[len - 1].toUpperCase();

console.log(result);

Java

public class ChangeCase {
    public static void main(String[] args) {
        String name = "priya";
        int len = name.length();
        int mid = len / 2;

        // Build the new string
        String result = 
            name.substring(0, 1).toUpperCase() +          // First character uppercase
            name.substring(1, mid) +                      // Characters from 1 to middle-1 unchanged
            name.substring(mid, mid + 1).toUpperCase() + // Middle character uppercase
            name.substring(mid + 1, len - 1) +           // Characters after middle to second last unchanged
            name.substring(len - 1).toUpperCase();       // Last character uppercase

        System.out.println(result);
    }
}