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Kendhall Lebron Ruiz
Courses Plus Student 1,143 PointsI don't understand the drive method
It's asking "Modify the drive method to define a parameter of how many laps should be driven. Update the method body to handle the new parameter." I know I have to use the += and -= thing but I don't know how to use them here. I already got the right answer but I guessed it. An explanation would be appreciated.
class GoKart {
public static final int MAX_BARS = 8;
private String color;
private int barCount;
private int lapsDriven;
public GoKart(String color) {
this.color = color;
}
public String getColor() {
return color;
}
public void charge() {
barCount = MAX_BARS;
}
public boolean isBatteryEmpty() {
return barCount == 0;
}
public boolean isFullyCharged() {
return MAX_BARS == barCount;
}
public void drive() {
lapsDriven++;
barCount--;
}
}
1 Answer
![Steven Parker](https://uploads.teamtreehouse.com/production/profile-photos/969492/micro_tool_chess_set_2.jpg)
Steven Parker
230,688 PointsYou say that you "got the right answer", but it's not shown here. This is the code the challenge starts with.
But to explain the "+= and -= thing", those are the increment and decrement operators. Both of them change the value of the term on the left by the amount represented on the right. So "dogs += 3
" would raise the count of "dogs" by 3, and "students -= seniors
" would decrease the current student count by the number of folks who are graduating (the senior class).