end of Sprit-1

Author: PandiSimatupang

Sprint-2/1-key-errors/0.js

@@ -1,13 +1,21 @@
 // Predict and explain first...
 //  =============> write your prediction here
+//the function will turn the first given string into Uppercase.
 
 // call the function capitalise with a string input
 // interpret the error message and figure out why an error is occurring
 
 function capitalise(str) {
-  let str = `${str[0].toUpperCase()}${str.slice(1)}`;
-  return str;
+  let strWithUpperCase = `${str[0].toUpperCase()}${str.slice(1)}`;
+  return strWithUpperCase;
 }
 
 // =============> write your explanation here
+// str[0].toUpperCase() ---> gets the first character and uses build-in method to convert a char to uppercase
+// str.slice(1) ----> will slice the array or sting "start from 1" to the rest of array or string
+// we get an error because we "re-declare" the str variable as parameter and as call back of expression
+
 // =============> write your new code here
+
+const myStr = "i forgot add this string";
+console.log(capitalise(myStr));

Sprint-2/1-key-errors/1.js

@@ -2,17 +2,24 @@
 
 // Why will an error occur when this program runs?
 // =============> write your prediction here
-
+// decimalNumber variable was declared twice. First as parameter and second as const in function body
+// use different variable name, either in parameter or the one in function body.
+// any way this function always return the same value because the variable is constant and define inside th function,
+// usually a function take a variable from function parameters.
+// console.log() will fail to print because no parameter define first.
 // Try playing computer with the example to work out what is going on
 
 function convertToPercentage(decimalNumber) {
-  const decimalNumber = 0.5;
+  //-----> should be place as parameter and not as a constant ,,,,,const decimalNumber = 0.5;
   const percentage = `${decimalNumber * 100}%`;
 
   return percentage;
 }
 
-console.log(decimalNumber);
+decimalNumber = 0.27;
+
+console.log(decimalNumber); //this is fine, just define the parameter it needs.
+console.log(convertToPercentage(decimalNumber));
 
 // =============> write your explanation here
 

Sprint-2/1-key-errors/2.js

@@ -1,20 +1,27 @@
-
 // Predict and explain first BEFORE you run any code...
 
 // this function should square any number but instead we're going to get an error
 
 // =============> write your prediction of the error here
+//the function will return square for every given number.
 
-function square(3) {
-    return num * num;
-}
+// function square(3) {
+//     return num * num;
+// }
 
 // =============> write the error message here
+// ans: Unexpected number
 
 // =============> explain this error message here
-
+// ans: function need num to be defined, instead parameter was given 3 as literal value that does not point to any variable as parameter
 // Finally, correct the code to fix the problem
 
 // =============> write your new code here
 
+function square(num) {
+  return num * num;
+}
+
+mynum = 3; //define the num
 
+console.log(square(mynum)); //verify the result

Sprint-2/2-mandatory-debug/0.js

@@ -1,14 +1,20 @@
 // Predict and explain first...
 
 // =============> write your prediction here
+// function will return with result of multiplication of given parameters (i,e: a times b)
+// function multiply(a, b) {
+//   console.log(a * b);
+// }
 
-function multiply(a, b) {
-  console.log(a * b);
-}
-
-console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
+// console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
 
 // =============> write your explanation here
-
+// the function does not return any thing, so as result ${multiply(10, 32)} --> will return as "undefined"
 // Finally, correct the code to fix the problem
 //  =============> write your new code here
+
+function multiply(a, b) {
+  return a * b;
+}
+
+console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);

Sprint-2/2-mandatory-debug/1.js

@@ -1,13 +1,23 @@
 // Predict and explain first...
 //  =============> write your prediction here
+// sure this function wont work because, hang on.. I should predict and pretend that everything is fine
+// the function will return with summary of given parameters and console.log will verify it
 
-function sum(a, b) {
-  return;
-  a + b;
-}
+// function sum(a, b) {
+//   return;
+//   a + b;
+// }
 
-console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
+// console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
 
 // =============> write your explanation here
+//function will execute line the code and escape from the function block whenever it "sees" return.. it will return with any expression put on it
+// in this function a+b which is expected as the result is placed after return line because return has ";" so i wont bother look the next line.
+// just remove the semicolon next to the return.. and put a+b instead, because some how "prettier" as trusty worthy formatter for this course will always add extra ; for every logical expression (somehow).. :) xixixixi
 // Finally, correct the code to fix the problem
 //  =============> write your new code here
+function sum(a, b) {
+  return a + b;
+}
+
+console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);

Sprint-2/2-mandatory-debug/2.js

@@ -2,23 +2,42 @@
 
 // Predict the output of the following code:
 // =============> Write your prediction here
+// alright! from the sake of the function name, I can predict that it will successfully get the last digit
+// oh hang-on, where is the parameter???? this programmer must be tired or "coding while eating"... careful aye.. holiday is coming.
 
-const num = 103;
+// const num = 103;
 
-function getLastDigit() {
-  return num.toString().slice(-1);
-}
+// function getLastDigit() {
+//   return num.toString().slice(-1);
+// }
 
-console.log(`The last digit of 42 is ${getLastDigit(42)}`);
-console.log(`The last digit of 105 is ${getLastDigit(105)}`);
-console.log(`The last digit of 806 is ${getLastDigit(806)}`);
+// console.log(`The last digit of 42 is ${getLastDigit(42)}`);
+// console.log(`The last digit of 105 is ${getLastDigit(105)}`);
+// console.log(`The last digit of 806 is ${getLastDigit(806)}`);
 
 // Now run the code and compare the output to your prediction
 // =============> write the output here
+// nope.. It runs as predicted :) xixixiixi... that way we are in this "debugging" session.
+// it runs but no syntax error but the output are not correct.
+
 // Explain why the output is the way it is
 // =============> write your explanation here
+// the function does not get any "define parameter", like nothing, so it tries to the "num" in global variable
+// that is given just before the function that is const num = 103;
+// so, every time that function is called, it will use num 103 as parameter
+
 // Finally, correct the code to fix the problem
 // =============> write your new code here
+const num = 103;
+
+function getLastDigit(num) {
+  return num.toString().slice(-1);
+}
+
+console.log(`The last digit of 42 is ${getLastDigit(42)}`);
+console.log(`The last digit of 105 is ${getLastDigit(105)}`);
+console.log(`The last digit of 806 is ${getLastDigit(806)}`);
 
 // This program should tell the user the last digit of each number.
 // Explain why getLastDigit is not working properly - correct the problem
+// no syntax error just logic error :) because, sometime we need to manipulate the function just like that. BTW that is not save anyway.

Sprint-2/3-mandatory-implement/1-bmi.js

@@ -15,5 +15,17 @@
 // It should return their Body Mass Index to 1 decimal place
 
 function calculateBMI(weight, height) {
-    // return the BMI of someone based off their weight and height
-}
+  // squaring your height: 1.73 x 1.73 = 2.99
+  let heightSquared = height * height;
+  // dividing 70 by 2.99 = 23.41
+  let weightMod = weight / heightSquared;
+  // Your result will be displayed to 1 decimal place, for example 23.4.
+  let BMI = weightMod.toFixed(1);
+  // return the BMI of someone based off their weight and height
+  return BMI;
+}
+
+let myWeight = 70;
+let myHeight = 1.73;
+
+console.log(`my BMI is ${calculateBMI(myWeight, myHeight)}`);

Sprint-2/3-mandatory-implement/2-cases.js

@@ -14,3 +14,17 @@
 // You will need to come up with an appropriate name for the function
 // Use the MDN string documentation to help you find a solution
 // This might help https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/toUpperCase
+
+let myStr = "hello world I am sleepy";
+
+// let myStrUpperCase = myStr.toUpperCase();
+
+// let arrWord = myStrUpperCase.split(" ");
+
+// let myStrUpperCaseWithSnakeCase = arrWord.join("_");
+
+//console.log(`${arrWord}`);
+
+let combine = myStr.toUpperCase().split(" ").join("_");
+
+console.log(`${combine}`);

Sprint-2/3-mandatory-implement/3-to-pounds.js

@@ -4,3 +4,66 @@
 // You will need to declare a function called toPounds with an appropriately named parameter.
 
 // You should call this function a number of times to check it works for different inputs
+
+//=============================================================
+// const penceString = "9p"; //init variable
+
+// const penceStringWithoutTrailingP = penceString.substring(
+//   0,
+//   penceString.length - 1
+// ); //remove p character at the end of the variable
+// console.log(penceStringWithoutTrailingP);
+
+// const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0"); //
+// console.log(paddedPenceNumberString); //give format of 3 zeroes if the number is less than 3 digits.
+
+// const pounds = paddedPenceNumberString.substring(
+//   0,
+//   paddedPenceNumberString.length - 2
+// ); //get ponds value conversion changes for given pence
+
+// console.log(pounds);
+
+// const pence = paddedPenceNumberString
+//   .substring(paddedPenceNumberString.length - 2)
+//   .padEnd(2, "0"); //get the reminds after conversion to pounds
+
+// console.log(`£${pounds}.${pence}`);
+
+//------------------------------------------------------------------------------------------
+
+function pensToPounds(penceString) {
+  const penceStringWithoutTrailingP = penceString.substring(
+    0,
+    penceString.length - 1
+  ); //remove p character at the end of the variable
+  //console.log(penceStringWithoutTrailingP);
+
+  const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0"); //
+  //console.log(paddedPenceNumberString); //give format of 3 zeroes if the number is less than 3 digits.
+
+  const pounds = paddedPenceNumberString.substring(
+    0,
+    paddedPenceNumberString.length - 2
+  ); //get ponds value conversion changes for given pence
+
+  //console.log(pounds);
+
+  const pence = paddedPenceNumberString
+    .substring(paddedPenceNumberString.length - 2)
+    .padEnd(2, "0"); //get the reminds after conversion to pounds
+
+  return `£${pounds}.${pence}`;
+}
+
+//test----1
+let moneyA = "90p";
+console.log(`${pensToPounds(moneyA)}`);
+
+//test----2
+moneyA = "710p";
+console.log(`${pensToPounds(moneyA)}`);
+
+//test----3
+moneyA = "1210p";
+console.log(`${pensToPounds(moneyA)}`);