How does this return 3?

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#1

alan if block nonsense
alan if block nonsense1123×871 68.3 KB

I need a diagram. this doesn’t make any sense to me

#2

So you’re starting with 4 variables.

let scoreOfAlan = 5;
let scoreOfJudy = 3;
let foulsCommittedByJudy = 1;
let foulsCommittedByAlan = 2;

Then, the condition on the first if is true, because foulsCommittedByJudy has a value of 1 which is bigger than 0:

if (foulsCommittedByJudy > 0) // condition is true

Which means the line of code inside the if is executed:

scoreOfJudy = scoreOfJudy - foulsCommittedByJudy;

In this line, scoreOfJudy is set with a new value; Which is the current value (3) minus the value of foulsCommittedByJudy (1). So the new value of scoreOfJudy is 2.

And like in the first if, the condition on the second one is true, because foulsCommittedByAlan has a value of 2 which is bigger than 0:

if (foulsCommittedByAlan > 0) // condition is true

Which means the line of code inside this if is executed as well:

scoreOfAlan = scoreOfAlan - foulsCommittedByAlan;

scoreOfAlan is set with a new value; Which is the current value (5) minus the value of foulsCommittedByAlan (2). So the new value of scoreOfAlan is 3.

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#3

the if block resets the value of scoreOfAlan and then executes with the new value?
if the question was looking for the number 2, the answer would be scoreOfJudy?
if I am understanding the logic correctly?

#4

The if block doesn’t reset the value; It checks for a condition (which is inside parentheses). Then, if the condition is true (or truthy), the line of code inside the if block is executed (between the curly brackets). If the condition is false (or falsy), the statement is not executed. So in our case:

if (foulsCommittedByJudy > 0) {
  scoreOfJudy = scoreOfJudy - foulsCommittedByJudy;
}

The condition inside the parentheses is like a question. It asks: “does the current value of committedByJudy is bigger than 0?”
Because the value of committedByJudy is 1, the condition evaluates as true; and the line inside the if block is executed. in our case it’s scoreOfJudy = scoreOfJudy - foulsCommittedByJudy;.

This line is the one that sets a new value to scoreOfJudy, Which is the current value ( 3 ) minus the value of foulsCommittedByJudy ( 1 ). So the new value of scoreOfJudy is 2.

The same goes for the second if block. So yes, if the question was looking for the number 2, the answer would be scoreOfJudy.

For more info on if...else statements, I recommend maybe repeating the lesson on Codecademy, or check out MDN.

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