Substring range and point

Author: Arthur

Sprint-1/3-mandatory-interpret/1-percentage-change.js

@@ -2,7 +2,7 @@ let carPrice = "10,000";
 let priceAfterOneYear = "8,543";
 
 carPrice = Number(carPrice.replaceAll(",", ""));
-priceAfterOneYear = Number(priceAfterOneYear.replaceAll("," ""));
+priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",", ""));
 
 const priceDifference = carPrice - priceAfterOneYear;
 const percentageChange = (priceDifference / carPrice) * 100;
@@ -12,11 +12,33 @@ console.log(`The percentage change is ${percentageChange}`);
 // Read the code and then answer the questions below
 
 // a) How many function calls are there in this file? Write down all the lines where a function call is made
+There are 4 function calls here. There are two when you use Number();
+ The other call is about console.log() to print the string out.
+ When you call the variable (priceDifference/ carPrice), it is a function call. 
+The last one is
 
 // b) Run the code and identify the line where the error is coming from - why is this error occurring? How can you fix this problem?
 
+It shows that I miss a ) parenthesis.
+
+
 // c) Identify all the lines that are variable reassignment statements
 
+carPrice = Number(carPrice.replaceAll(",", ""));
+priceAfterOneYear = Number(priceAfterOneYear.replaceAll("," ""));
+
 // d) Identify all the lines that are variable declarations
 
-// e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+let carPrice = "10,000";
+let priceAfterOneYear = "8,543";
+
+const priceDifference = carPrice - priceAfterOneYear;
+const percentageChange = (priceDifference / carPrice) * 100;
+
+// e) Describe what is the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+
+It deletes all the comma insides.I
+The Number helps convert that string into an actual figure.
+
+
+

Sprint-1/3-mandatory-interpret/2-time-format.js

@@ -12,14 +12,31 @@ console.log(result);
 // For the piece of code above, read the code and then answer the following questions
 
 // a) How many variable declarations are there in this program?
+ Six, the const with the functions inside.
+
 
 // b) How many function calls are there?
+4
 
 // c) Using documentation, explain what the expression movieLength % 60 represents
 // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators
 
+It is called the remaining function, because if you use this function , you will use the remainingMinutes to divides 60 and get the remaining value .
+
+
 // d) Interpret line 4, what does the expression assigned to totalMinutes mean?
+It calls the variable movieLength and remainingSeconds and substract together and divide it 60.
+
+
 
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
+I think it represents the total hour , remaining minutes and the remaining seconds .Duration is a better name
+
+
 
 // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+yes
+I tried to put 6(second), 60(1 minute), 3600(equivalent to 1 hour)
+
+
+

Sprint-1/3-mandatory-interpret/3-to-pounds.js

@@ -24,4 +24,17 @@ console.log(`£${pounds}.${pence}`);
 // Try and describe the purpose / rationale behind each step
 
 // To begin, we can start with
-// 1. const penceString = "399p": initialises a string variable with the value "399p"
+
+line 1. const penceString = "399p": initialises a string variable with the value "399p"
+line 3. You define a penceStringWithoutTrailingP variable and call a function to cut a line, you use penceString.length -1 because 
+you want to cut the p. 
+
+line 8: You define a variable paddedPenceNumberString and call a function to add 0 into the letters, if the words are not three characters long.
+line 9: You want to take the pound out of 399, so you call the function substring and only wants before the index 1, which is calculated by (0 , length -2); 
+
+line 14: You call a variable function and you subtract the value from index 1 to the end. 
+line 18: print the variable pound and the variable pence with the . 
+
+
+
+