Completed Week-2 -> week-2-js -> easy assignment

week-2/week-2-async-js/easy/1-counter.js

@@ -0,0 +1,4 @@
+let count = 1;
+setInterval(() => {
+   console.log(`${count++}`); 
+}, 1000);

week-2/week-2-async-js/easy/2-counter.js

@@ -0,0 +1,7 @@
+let count = 1;
+function counter(){
+    console.log(`${count++}`);
+    setTimeout(counter, 1000);
+}
+
+counter()

week-2/week-2-async-js/easy/3-read-from-file.js

@@ -0,0 +1,12 @@
+const fs = require("fs");
+
+const content = fs.readFile('a.txt', 'utf-8', (err, data) => {
+    console.log(`File Content:\n${data}`);    
+})
+
+console.log("Expensive Operation ongoing...");
+for(i=0; i<1000000000; i++){
+
+}
+console.log("Expensive Operation done.\n");
+

week-2/week-2-async-js/easy/4-write-to-file.js

@@ -0,0 +1,7 @@
+const fs = require("fs");
+
+fs.writeFile("a.txt", "Hey this is just another follow up!", "utf-8", () => {
+    console.log("Done.");
+});
+
+console.log("Writing to file ...");

week-2/week-2-async-js/easy/a.txt

@@ -0,0 +1 @@
+Hey this is just another follow up!

week-2/week-2-async-js/hard (promises)/1-promisify-setTimeout.js

@@ -3,6 +3,9 @@
 */
 
 function wait(n) {
+    return new Promise((resolve, reject) => {
+        setTimeout( resolve, n * 1000);
+    });
 }
 
 module.exports = wait;

week-2/week-2-async-js/hard (promises)/2-sleep-completely.js

@@ -5,6 +5,12 @@
  */
 
 function sleep(milliseconds) {
+    return new Promise((resolve, reject) => {
+        const startTime = new Date().getTime();
+        while (new Date().getTime() < startTime + milliseconds) {
+            resolve();
+        }
+    });
 }
 
 module.exports = sleep;

week-2/week-2-async-js/hard (promises)/3-promise-all.js

@@ -5,19 +5,21 @@
  */
 
 function wait1(t) {
-
+    return new Promise((resolve) => setTimeout(resolve, t * 1000));
 }
 
 function wait2(t) {
-
+    return new Promise((resolve) => setTimeout(resolve, t * 1000));
 }
 
 function wait3(t) {
-
+    return new Promise((resolve) => setTimeout(resolve, t * 1000));
 }
 
-function calculateTime(t1, t2, t3) {
-
+async function calculateTime(t1, t2, t3) {
+    const startTime = Date.now();
+    await Promise.all([wait1(t1), wait2(t2), wait3(t3)]);
+    return Date.now() - startTime;
 }
 
 module.exports = calculateTime;

week-2/week-2-async-js/hard (promises)/4-promise-chain.js

@@ -6,19 +6,33 @@
  */
 
 function wait1(t) {
-
+    return new Promise((resolve) => setTimeout(resolve, t * 1000));
 }
 
 function wait2(t) {
-
+    return new Promise((resolve) => setTimeout(resolve, t * 1000));
 }
 
 function wait3(t) {
-
+    return new Promise((resolve) => setTimeout(resolve, t * 1000));
 }
 
 function calculateTime(t1, t2, t3) {
+    const startTime = Date.now();
+
+    return call(t1, t2, t3).then(() => {
+        return Date.now() - startTime;
+    });
+}
 
+function call(t1, t2, t3) {
+    return wait1(t1)
+        .then(() => {
+            return wait2(t2);
+        })
+        .then(() => {
+            return wait3(t3);
+        });
 }
 
 module.exports = calculateTime;

week-2/week-2-async-js/medium/1-file-cleaner.js

@@ -0,0 +1,17 @@
+const fs = require('fs');
+
+fs.readFile('a.txt', 'utf-8', (err, data) => {
+    console.log(`Before clening: \n${data}`);
+    cleanFile(data);    
+})
+
+function cleanFile(content){
+    content = content.replace(/\s{2,}/g, ' ')
+    fs.writeFile('a.txt', content, 'utf-8', () => {
+        console.log('File cleaned!');
+        fs.readFile("a.txt", "utf-8", (err, data) => {
+            console.log(data);
+        });
+
+    })
+}

week-2/week-2-async-js/medium/2-clock.js

@@ -0,0 +1,34 @@
+const date = new Date();
+setInterval(() => {
+    console.log(
+        `24 Hour Format - ${date
+            .getHours()
+            .toString()
+            .padStart(2, "0")}:${date
+            .getMinutes()
+            .toString()
+            .padStart(2, "0")}:${date
+            .getSeconds()
+            .toString()
+            .padStart(2, "0")}`
+    );
+    //12 hour format
+    const hour =
+        date.getHours() - 12 < 0
+            ? date.getHours() == 0
+                ? 12
+                : date.getHours()
+            : date.getHours() - 12;
+    const flag = date.getHours() > 11 ? "PM" : "AM";
+    console.log(
+        `12 Hour Format - ${hour
+            .toString()
+            .padStart(2, "0")}:${date
+            .getMinutes()
+            .toString()
+            .padStart(2, "0")}:${date
+            .getSeconds()
+            .toString()
+            .padStart(2, "0")} ${flag}`
+    );
+}, 1000);

week-2/week-2-async-js/medium/a.txt

@@ -0,0 +1 @@
+Hi this is TankCodes.

week-2/week-2-js/easy/anagram.js

@@ -5,7 +5,14 @@
 */
 
 function isAnagram(str1, str2) {
-
+    function sortString(str) {
+        return str.toLowerCase().split("").sort().join("").replace(/\s/g, "");
+    }
+    return (sortString(str1) === sortString(str2)) 
 }
 
+console.log(isAnagram("spar", "raps")); //true
+console.log(isAnagram("spar", "rpas")); //true
+console.log(isAnagram("new york times", "monkeys write")); //true
+
 module.exports = isAnagram;

week-2/week-2-js/easy/expenditure-analysis.js

@@ -12,9 +12,144 @@
 	}
   Output - [{ category: 'Food', totalSpent: 10 }] // Can have multiple categories, only one example is mentioned here
 */
+//Brute force
+/* function calculateTotalSpentByCategory(transactions) {
+	let totalSpent = []
+	for (const transaction of transactions) {
+		let flag = true;
+		for(const category of totalSpent){
+			if (transaction.category === category.category){
+				category.totalSpent += transaction.price
+				flag = false
+			}
+		}
+		if (flag){
+			const newCategory = {
+				category: transaction.category,
+				totalSpent: transaction.price
+			}
+			totalSpent.push(newCategory);
+		}
+	}
+  	return totalSpent;
+} */
 
-function calculateTotalSpentByCategory(transactions) {
-  return [];
+//Optimized
+function calculateTotalSpentByCategory(transactions){
+	const categoryTotals = {}
+	for(const transaction of transactions){
+		categoryTotals[transaction.category] = (categoryTotals[transaction.category] || 0) + transaction.price
+	}
+	const result = [];
+	for(const category in categoryTotals){
+		result.push({
+			category: category,
+			totalSpent: categoryTotals[category]
+		})
+	}
+	return result
 }
 
+const transactions = [
+    {
+        id: 1,
+        timestamp: 1656076800000,
+        price: 149,
+        category: "Food",
+        itemName: "Dinner",
+    },
+    {
+        id: 2,
+        timestamp: 1656076800000,
+        price: 110,
+        category: "Food",
+        itemName: "Lunch",
+    },
+    {
+        id: 3,
+        timestamp: 1656076800000,
+        price: 459,
+        category: "Entertainment",
+        itemName: "Movie",
+    },
+    {
+        id: 4,
+        timestamp: 1656076800000,
+        price: 30,
+        category: "Food",
+        itemName: "Snacks",
+    },
+    {
+        id: 5,
+        timestamp: 1656076800000,
+        price: 20,
+        category: "Transport",
+        itemName: "Train",
+    },
+    {
+        id: 6,
+        timestamp: 1656076800000,
+        price: 200,
+        category: "Food",
+        itemName: "Dinner",
+    },
+    {
+        id: 7,
+        timestamp: 1656076800000,
+        price: 50,
+        category: "Food",
+        itemName: "Lunch",
+    },
+    {
+        id: 8,
+        timestamp: 1656076800000,
+        price: 340,
+        category: "Food",
+        itemName: "Pizza",
+    },
+    {
+        id: 9,
+        timestamp: 1656076800000,
+        price: 200,
+        category: "Entertainment",
+        itemName: "Movie",
+    },
+    {
+        id: 10,
+        timestamp: 1656076800000,
+        price: 15,
+        category: "Transport",
+        itemName: "Train",
+    },
+    {
+        id: 11,
+        timestamp: 1656076800000,
+        price: 15,
+        category: "Transport",
+        itemName: "Bus",
+    },
+    {
+        id: 12,
+        timestamp: 1656076800000,
+        price: 249,
+        category: "Entertainment",
+        itemName: "Netflix",
+    },
+    {
+        id: 13,
+        timestamp: 1656076800000,
+        price: 30,
+        category: "Transport",
+        itemName: "Auto",
+    },
+    {
+        id: 14,
+        timestamp: 1656076800000,
+        price: 100,
+        category: "Food",
+        itemName: "Momos",
+    },
+];
+console.log(calculateTotalSpentByCategory(transactions));
+
 module.exports = calculateTotalSpentByCategory;

week-2/week-2-js/easy/findLargestElement.js

@@ -6,7 +6,16 @@
 */
 
 function findLargestElement(numbers) {
-
+    let result = numbers[0];
+    for(const number of numbers){
+        if (number > result){
+            result = number;
+        }
+    }
+    return result
 }
+const numbers = [1, 2, 3, 4, 5, 6, 1, 3, 99, 1, 3, 4234, 5, 2];
+console.log(findLargestElement(numbers));
+
 
 module.exports = findLargestElement;