Main 1

01-js/easy/expenditure-analysis.js

@@ -8,8 +8,40 @@
   - `npm run test-expenditure-analysis`
 */
 
-function calculateTotalSpentByCategory(transactions) {
-  return [];
+
+function solve(transactions) {
+  var spendEstimates = {};
+  for (var i = 0; i < transactions.length; i++) {
+    var t = transactions[i];
+    if (spendEstimates[t.category]) {
+      spendEstimates[t.category] = spendEstimates[t.category] + t.price;
+    } else {
+      spendEstimates[t.category] = t.price;
+    }
+  }
+  console.log(spendEstimates);
 }
 
-module.exports = calculateTotalSpentByCategory;
+const transactions = [
+  {
+    category: "food",
+    itemNames: "maggi",
+    price: 20,
+    timestamp: "2023-06-01T10:30:00Z",
+  },
+  {
+      category: "drink",
+    itemNames: "coke",
+    price: 40,
+    timestamp: "2023-06-01T10:30:00Z",
+  },
+  {
+      category: "drink",
+    itemNames: "lassi",
+    price: 50,
+    timestamp: "2023-06-01T10:30:00Z",
+  },
+];
+
+
+solve(transactions)

02-async-js/easy/3-read-from-file.md

@@ -1,7 +1,18 @@
-## Reading the contents of a file
+const fs = require('fs')
 
-Write code to read contents of a file and print it to the console. 
-You can use the fs library to as a black box, the goal is to understand async tasks. 
-Try to do an expensive operation below the file read and see how it affects the output. 
-Make the expensive operation more and more expensive and see how it affects the output. 
+// async way of readin a file 
+fs.readFile('read.txt', 'utf8', (err, data) => {
+  if (err) {
+    console.error('Error reading file:', err);
+    return;
+  }
+  console.log('File contents:', data);
+});
 
+// Synchronous file read
+try {
+  const data = fs.readFileSync('read.txt', 'utf8');
+  console.log('File contents:', data);
+} catch (err) {
+  console.error('Error reading file:', err);
+}

02-async-js/easy/4-write-to-file.md

@@ -1,3 +1,24 @@
 ## Write to a file
 Using the fs library again, try to write to the contents of a file.
-You can use the fs library to as a black box, the goal is to understand async tasks.
+You can use the fs library to as a black box, the goal is to understand async tasks.
+
+const fs = require('fs');
+
+// Asynchronous file write
+const data = 'Hello, World!';
+fs.writeFile('read.txt', data, (err) => {
+  if (err) {
+    console.error('Error writing file:', err);
+    return;
+  }
+  console.log('File written successfully!');
+});
+
+// Synchronous file write
+try {
+  const data = 'Hello, World!';
+  fs.writeFileSync('read.txt', data);
+  console.log('File written successfully!');
+} catch (err) {
+  console.error('Error writing file:', err);
+}

02-async-js/medium/1-file-cleaner.md

@@ -10,4 +10,18 @@ After the program runs, the output should be
 
 ```
 hello world my name is raman
-```
+
+```
+
+
+const fs = require('fs')
+
+// async way of readin a file 
+fs.readFile('read.txt', 'utf8', (err, data) => {
+  if (err) {
+    console.error('Error reading file:', err);
+    return;
+  }
+  const data1 = data.replace(/\s+/g, ' ');
+  console.log('File contents:', data1);
+});