Arrays with for loops

[philip1999]

Array testGrades contains NUM_VALS test scores. Write a for loop that sets sumExtra to the total extra credit received. Full credit is 100, so anything over 100 is extra credit. Ex: If testGrades = {101, 83, 107, 90}, then sumExtra = 8, because 1 + 0 + 7 + 0 is 8.

  #include <iostream>
using namespace std;

int main() {
   const int NUM_VALS = 4;
   int testGrades[NUM_VALS];
   int i;
   int sumExtra = -9999; // Assign sumExtra with 0 before your for loop

   testGrades[0] = 101;
   testGrades[1] = 83;
   testGrades[2] = 107;
   testGrades[3] = 90;
   
sumExtra=0;

   for(int i=0;i<NUM_VALS;++i)
   {
      if (testGrades[i]>100)
      {
         sumExtra=sumExtra+ (testGrades[i]/100);
      }
   }

   cout << "sumExtra: " << sumExtra << endl;
   return 0;
}

I tried the above code but still don't understand where I made a mistake.

[Repeater]

(testGrades[i]/100);

This is wrong.

If you have the number 107, and you want to get from it the number 7, the calculation 107/100 is not the right calculation to make.

[jonnin]

This looks like program 1 for a new semester...
% operator, look that up for a hint (this is the correct way to do it)

You can also cook up messy DIY logic along the lines of
extra = ( (value - 100) > 0)*(value - 100); (not recommended).

[philip1999]

@Repeater

When I replaced (testGrades[i]/100); with (testGrades[i]-100); it worked. I don't understand the reason behind it.