01-js done

week-1/Week-1-assignment-with-tests/01-js/easy/anagram.js

@@ -8,7 +8,25 @@
 */
 
 function isAnagram(str1, str2) {
+
 
+
+    if(str1.length != str2.length){
+    return false;
+    }
+
+
+  str1 = str1.toLowerCase();
+  str2 = str2.toLowerCase();
+
+  str1 = str1.split('').sort().join('');
+  str2 = str2.split('').sort().join('');
+  if(str1 == str2){
+    return true;
+  }
+  else{
+    return false;
+  }
 }
 
 module.exports = isAnagram;

week-1/Week-1-assignment-with-tests/01-js/easy/expenditure-analysis.js

@@ -9,7 +9,24 @@
 */
 
 function calculateTotalSpentByCategory(transactions) {
-  return [];
+  var returnElement = [];
+
+  transactions.forEach((traEle) => {
+    ///go through each and every element in transactions
+    var elemen = returnElement.find((ele) => (ele.category === traEle.category));
+    ///check if that element is present
+    if (elemen) {
+      elemen.totalSpent = elemen.totalSpent + traEle.price;
+    } else {
+      returnElement.push({ category: traEle.category, totalSpent: traEle.price });
+    }
+  });
+
+
+
+  return returnElement;
 }
+
+
 
 module.exports = calculateTotalSpentByCategory;

week-1/Week-1-assignment-with-tests/01-js/hard/calculator.js

@@ -17,6 +17,51 @@
   - `npm run test-calculator`
 */
 
-class Calculator {}
+class Calculator {
+  constructor() {
+    this.result = 0;
+  }
 
+  add(number) {
+    this.result += number;
+  }
+
+  subtract(number) {
+    this.result -= number;
+  }
+
+  multiply(number) {
+    this.result *= number;
+  }
+
+  divide(number) {
+    if (number == 0) {
+      throw new Error("Cannot be divided by 0");
+    }
+
+    this.result /= number;
+  }
+
+  clear() {
+    this.result = 0;
+  }
+
+  getResult() {
+    return this.result;
+  }
+
+  calculate(expression) {
+    expression = expression.replace(/\s+/g, "");
+
+    this.result = eval(expression);
+
+    if (isNaN(this.result)) {
+      throw new Error("Invalid expression");
+    } else if (this.result === Infinity) {
+      throw new Error("Cannot be divided by 0");
+    }
+  }
+
+}
+var calc = new Calculator();
 module.exports = Calculator;

week-1/Week-1-assignment-with-tests/01-js/hard/todo-list.js

@@ -12,7 +12,32 @@
 */
 
 class Todo {
-
+  constructor() {
+    this.todos = []
+  }
+  add(todo) {
+    this.todos.push(todo)
+  }
+  remove(indexOfTodo) {
+    this.todos.splice(indexOfTodo, 1)
+  }
+  update(indexOfTodo, updatedTodo) {
+    if (indexOfTodo < this.todos.length) {
+      this.todos[indexOfTodo] = updatedTodo
+    }
+  }
+  getAll() {
+    return this.todos
+  }
+  get(indexOfTodo) {
+    if (indexOfTodo >= this.todos.length) {
+      return null
+    }
+    return this.todos[indexOfTodo]
+  }
+  clear() {
+    this.todos.splice(0)
+  }
 }
 
 module.exports = Todo;

week-1/Week-1-assignment-with-tests/01-js/medium/palindrome.js

@@ -5,9 +5,12 @@
   Once you've implemented the logic, test your code by running
   - `npm run test-palindrome`
 */
-
+const basic = (str) => String(str).toLowerCase().replace(/[^\w]/g, '')
 function isPalindrome(str) {
-  return true;
+  const str1 = basic(str);
+  const str2 = basic(str).split('').reverse().join('')
+  console.log(str1,str2)
+  return str1 ===str2;
 }
 
 module.exports = isPalindrome;

week-1/Week-1-assignment-with-tests/01-js/medium/times.js

@@ -8,5 +8,15 @@ Hint - use Date class exposed in JS
 */
 
 function calculateTime(n) {
-    return 0.01;
-}
+    let start = Date.now()
+    let sum = 0
+    for (let i = 1; i <= n; i++) {
+      sum += i
+    }
+    console.log(sum)
+    let timeTaken = (Date.now() - start) / 1000
+    return timeTaken
+  }
+
+
+  console.log(calculateTime(100))

week-1/Week-1-assignment-with-tests/02-async-js/easy/1-counter.js

@@ -0,0 +1,6 @@
+let i = 1; 
+
+setInterval(() => {
+  console.log(i);
+  i++; 
+}, 1000); 

week-1/Week-1-assignment-with-tests/02-async-js/easy/1-counter.md

@@ -1,4 +1,5 @@
 ## Create a counter in JavaScript
 
 We have already covered this in the second lesson, but as an easy recap try to code a counter in Javascript
-It should go up as time goes by in intervals of 1 second
+It should go up as time goes by in intervals of 1 second
+

week-1/Week-1-assignment-with-tests/02-async-js/easy/2-counter.js

@@ -0,0 +1,9 @@
+let i = 0;
+
+function counter() {
+  console.log(i);
+  i++;
+  setTimeout(counter, 1000);
+}
+
+counter(); 

week-1/Week-1-assignment-with-tests/02-async-js/easy/3-read-from-file.js

@@ -0,0 +1,9 @@
+const fs = require('fs');
+fs.readFile('a.txt','utf-8',function(err,data){
+            if(err){
+               console.log(err);
+            }
+            else{
+               console.log(data);
+            }
+})

week-1/Week-1-assignment-with-tests/02-async-js/easy/4-write-to-file.js

@@ -0,0 +1,21 @@
+const fs = require('fs');
+
+fs.writeFile('a.txt', 'This is the content written to the file.', 'utf-8', (error) => {
+  if (error) {
+    console.error('Error writing to file:', error);
+    return;
+  }
+  console.log('File has been written successfully.');
+});
+
+console.log('This will execute before the write callback due to async nature.');
+
+
+console.log('Starting expensive operation...');
+let sum = 0;
+for (let i = 0; i < 1e8; i++) {
+  sum += i;
+}
+console.log('Expensive operation completed. Sum:', sum);
+
+console.log('Code execution continues after write task is initiated.');

week-1/Week-1-assignment-with-tests/02-async-js/easy/a.txt

@@ -0,0 +1 @@
+This is the content written to the file.

week-1/Week-1-assignment-with-tests/02-async-js/hard (promises)/1-promisify-setTimeout.js

@@ -3,4 +3,8 @@
 */
 
 function wait(n) {
-}
+    return new Promise(resolve => {
+      setTimeout(resolve, n * 1000);  
+    });
+  }
+

week-1/Week-1-assignment-with-tests/02-async-js/hard (promises)/2-sleep-completely.js

@@ -2,7 +2,15 @@
  * Write a function that halts the JS thread (make it busy wait) for a given number of milliseconds.
  * During this time the thread should not be able to do anything else.
  */
+function sleep(milliseconds) {
+               const start = Date.now();
+               while (Date.now() - start < milliseconds) {
+
+               }
+             }
 
-function sleep (seconds) {
-
-}
+
+             console.log("Start");
+             sleep(2000); 
+             console.log("End");
+

week-1/Week-1-assignment-with-tests/02-async-js/hard (promises)/3-promise-all.js

@@ -4,19 +4,31 @@
  * Print how long it took for all 3 promises to resolve.
  */
 
-
 function waitOneSecond() {
-
-}
-
-function waitTwoSecond() {
-
-}
-
-function waitThreeSecond() {
-
-}
-
-function calculateTime() {
-
-}
+               return new Promise((resolve) => {
+                 setTimeout(resolve, 1000);
+               });
+             }
+
+             function waitTwoSecond() {
+               return new Promise((resolve) => {
+                 setTimeout(resolve, 2000);
+               });
+             }
+
+             function waitThreeSecond() {
+               return new Promise((resolve) => {
+                 setTimeout(resolve, 3000);
+               });
+             }
+
+             function calculateTime() {
+               const start = Date.now();
+               Promise.all([waitOneSecond(), waitTwoSecond(), waitThreeSecond()]).then(() => {
+                 const end = Date.now();
+                 console.log(`Time taken: ${(end - start) / 1000} seconds`);
+               });
+             }
+
+             calculateTime();
+

week-1/Week-1-assignment-with-tests/02-async-js/hard (promises)/4-promise-chain.js

@@ -6,17 +6,34 @@
  */
 
 function waitOneSecond() {
-
-}
-
-function waitTwoSecond() {
-
-}
-
-function waitThreeSecond() {
-
-}
-
-function calculateTime() {
-
-}
+               return new Promise(resolve => {
+                 setTimeout(resolve, 1000);
+               });
+             }
+
+             function waitTwoSecond() {
+               return new Promise(resolve => {
+                 setTimeout(resolve, 2000);
+               });
+             }
+
+             function waitThreeSecond() {
+               return new Promise(resolve => {
+                 setTimeout(resolve, 3000);
+               });
+             }
+
+             function calculateTime() {
+               const start = Date.now();
+
+               waitOneSecond()
+                 .then(() => waitTwoSecond())
+                 .then(() => waitThreeSecond())
+                 .then(() => {
+                   const end = Date.now();
+                   console.log(`Time taken: ${(end - start) / 1000} seconds`);
+                 });
+             }
+
+             calculateTime();
+

week-1/Week-1-assignment-with-tests/02-async-js/medium/1-file-cleaner.js

@@ -0,0 +1,25 @@
+const fs = require('fs');
+
+
+function cleanFile(filePath) {
+
+  fs.readFile(filePath, 'utf-8', (err, data) => {
+    if (err) {
+      console.error('Error reading the file:', err);
+      return;
+    }
+
+
+    const cleanedData = data.replace(/\s+/g, ' ').trim();
+
+    fs.writeFile(filePath, cleanedData, 'utf-8', (err) => {
+      if (err) {
+        console.error('Error writing to the file:', err);
+        return;
+      }
+      console.log('File has been cleaned successfully!');
+    });
+  });
+}
+
+cleanFile('input.txt');