IT2234P Web Services and Server Technologies

📚 A comprehensive collection of daily practical lessons for Web Services and Server Technologies course.

📋 Course Overview

This repository serves as a practical guide through various web services and server technologies. Each lesson is organized in dedicated folders containing both source code and visual outputs.

🗓️ Latest Session: JavaScript Array Operations & Advanced Concepts (March 17, 2025)

🎯 Learning Objectives

• Master array manipulation using push and pop operations
• Implement array traversal using forEach loops
• Develop algorithms for array comparison and analysis
• Find common elements between arrays
• Understand nested array operations
• Learn JSON object manipulation
• Practice array reversal techniques
• Implement array frequency analysis
• Find pairs that sum to a target value
• Analyze element frequency in arrays

💻 Code Examples & Implementations

1. Basic Array Operations

Array Push and Pop (Arrayoperationspushpop.js)

//Array operations
//push pop
arr3 = ['a','b','d'];
console.log(arr3);
arr3.push('e');
console.log(arr3);
arr3.pop();
console.log(arr3);

View Output

Array Initialization and Access (printarray.js)

//Array
//functio
let name = []; //array initialization
let score = [84, 92, 75, 68, 55, 95, 66, 89, 87, 74]; //array declaration
//accessing array element
console.log(score[0]);

View Output

2. Array Traversal Techniques

Using For Loop (printarrayusingforloop.js)

let score = [84, 92, 75, 68, 55, 95, 66, 89, 87, 74];
for(let i=0;i< score.length;i++)
{
    console.log(score[i]);
}

View Output

Using forEach Loop (printarrayusingforeachloop.js)

let score = [84, 92, 75, 68, 55, 95, 66, 89, 87, 74];
score.forEach((n)=>{
    console.log(n);
})

View Output

3. Advanced Array Operations

Finding Maximum Number (findmaxnumberinthearrayusingforeachloop.js)

//find max number in the array using foreach loop
let score = [84, 92, 75, 68, 55, 95, 66, 89, 87, 74];
let max = score[0];
score.forEach((n)=>{
    if(n>max)
    {
        max = n;
    }
});
console.log("Maximum number in the array is: " + max);

View Output

Finding Common Elements (findthecommonelementsbetweentwoarrays.js)

// Define the arrays
let a = [4, 5, 6, 3, 7];
let b = [8, 3, 2, 1, 5];

// Array to store common elements
let commonElements = [];

// Use forEach to find common elements
a.forEach(element => {
    if(b.includes(element)) {
        commonElements.push(element);
    }
});

// Display the result
console.log("Common elements between arrays:", commonElements);

View Output

Nested Array Operations (printthenestedarray.js)

// Print nested array using forEach loop
let nestedArray = [[1, 2, 3], [4, 5, 6], [7, 8, 9]];
nestedArray.forEach((n) => {
  n.forEach((m) => {
    console.log(m);
  });
});

View Output

Array Reversal (reversethearrayusingpushpop.js)

//reverse the array using push and pop
// a b c d -> d c b a
let arr = ['a','b','c','d'];
let arr2 = [];

while(arr.length > 0) {
    arr2.push(arr.pop());
}

console.log(arr2);

View Output

4. Array Analysis and Algorithms

Finding Pairs with Target Sum (findingpairsinanarraythatsumuptoatargetvalue.js)

// Example array and target
let arr = [1, 2, 3, 4, 5, 6];
let target = 7;

// Function to find pairs that sum up to target using forEach
function findPairs(arr, target) {
    let pairs = [];
    
    // Use forEach to iterate through each number
    arr.forEach((num1, index) => {
        // Only check numbers after the current number to avoid duplicates
        arr.slice(index + 1).forEach(num2 => {
            // If pair sums to target, add to results
            if(num1 + num2 === target) {
                pairs.push([num1, num2]);
            }
        });
    });
    
    return pairs;
}

View Output

Finding Most Frequent Element (findthemostfrequentelementinthearray.js)

const numbers = [4,8,3,4,3,2,1,8,4];

// Create a Map to store frequency
const numberCount = new Map();

// Count frequency of each number
numbers.forEach(number => {
    const currentCount = numberCount.get(number) || 0;
    numberCount.set(number, currentCount + 1);
});

// Find the most frequent number
let highestCount = 0;
let mostCommonNumber = null;

numberCount.forEach((count, number) => {
    if (count > highestCount) {
        highestCount = count;
        mostCommonNumber = number;
    }
});

View Output

5. JSON Operations and Data Analysis

Basic JSON Structure (JSON.js)

//JSON
//{key:value}
let student = {
    name: "John",
    age: 20,
    marks: 90,
    isPassed: true,
    address: {
        street: "123 Main St",
        city: "Anytown"
    }
};

View Output

📊 Implementation Summary

Category	File	Description	Output
Basic Array Operations	Arrayoperationspushpop.js	Basic array push/pop operations	View
Basic Array Operations	printarray.js	Array initialization and access	View
Array Traversal	printarrayusingforloop.js	Array traversal using for loop	View
Array Traversal	printarrayusingforeachloop.js	Array traversal using forEach	View
Array Analysis	findmaxnumberinthearrayusingforeachloop.js	Finding maximum value using forEach	View
Array Comparison	findthecommonelementsbetweentwoarrays.js	Finding common elements between arrays	View
Nested Arrays	printthenestedarray.js	Nested array traversal using forEach	View
Array Manipulation	reversethearrayusingpushpop.js	Array reversal using push/pop	View
Array Algorithms	findingpairsinanarraythatsumuptoatargetvalue.js	Finding pairs that sum to target	View
Array Analysis	findthemostfrequentelementinthearray.js	Finding most frequent element	View
JSON Operations	JSON.js	JSON object manipulation	View
Student Data Analysis	homework.js	Student data filtering and GPA analysis	View

🔍 Technical Notes

• All implementations are in pure JavaScript
• Extensive use of ES6+ array methods
• Each example includes comprehensive console output
• Visual outputs are captured for reference
• Consistent code formatting and naming conventions

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📖 Learning Path | 🛠️ Practical Examples | 📊 Visual Outputs