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iOS Object-Oriented Objective-C Tying it All Together Cumulative Review

Andre Robinson
PLUS
Andre Robinson
Courses Plus Student 6,057 Points
Posted by Andre Robinson
Andre Robinson
Courses Plus Student 6,057 Points

Please help

I'm having trouble with syntax error

variable_assignment.mm 
NSArray *temps = @[@75.5,@83.3,@96,@99.7];

  float average;
 float runningTotal;

  for (NSNumber in temps;)  average = temps++;  {
        average = runningTotal /[temps floatValue];
    }

2 Answers

jcorum
jcorum
71,830 Points
jcorum
jcorum
71,830 Points

Andre, you don't want to compute the average inside the loop. You need to get the total (runningTotal) of the items, and then do the division outside the loop:

    NSArray *temps = @[@75.5, @83.3, @96, @99.7];
    float average;
    float runningTotal;
    for (int i = 0; i < temps.count; i++) {
        runningTotal += [[temps objectAtIndex: i] floatValue];
    }
    average = runningTotal / temps.count;
Hannah Gaskins
Hannah Gaskins
14,572 Points
Hannah Gaskins
Hannah Gaskins
14,572 Points

Hey Andre,

I just finished this exercise here and think I can help.

The for in loop you have there needs to have a named value. You can call it anything, but in mine below I called it 'tempItems"

NSArray *temps = @[@75.5, @83.3, @96, @99.7];
float average;
float runningTotal;

for (NSNumber *tempItems in temps) {
  runningTotal += [tempItems floatValue] ;
}

average = runningTotal/temps.count;

Hope that helps!