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iOS Objective-C Basics Scope and Loops For Loop

Ryan Maneo
Ryan Maneo
4,342 Points


In the video, it has a value of running total as 1275 after it finished its last iteration of the loop, why? Where the heck did 1275 come from?

1 Answer

Martin Wildfeuer
Martin Wildfeuer
Courses Plus Student 11,071 Points
int runningTotal = 0;

for (int = 1; i <= 50; i++) {
   runningTotal = runningTotal + i

the for loop will iterate over the numbers 1 to 50. With every loop the runningTotal is not incremented by the index, but runningTotal + 1. So the calculations would look like this:

// runningTotal = runningTotal + i

runningTotal = 0 + 1 // runningTotal is 0
runningTotal = 1 + 2 // runningTotal is now 3
runningTotal = 3 + 3 // runningTotal is now 6
runningTotal = 6 + 4 // runningTotal is now 10
// etc

So I have not calculated that through, but my guess is that runningTotal will be 1275 in the end.

Hope that helps :)