Lucía coaches the local junior athletics team. She has been with the same group for three years and knows every athlete by heart: who gives up too early, who pushes hardest in the final sprint, and who always shows up late to warm-up.
Every week, after training, Lucía sits on the bench with her worn notebook and writes down each athlete’s score for the day’s exercises. Scores range from 1 to 100.
The problem is that the team is never the same size. Some days athletes are absent due to illness, family plans, or just the winter cold. Some sessions have 6 athletes, others have 14.
Last week, the regional federation asked for the weekly team average to apply for a sports equipment grant. Lucía spent half an hour adding and dividing with a calculator — until her niece Marta, a computer science student, saw her from the doorway:
“Auntie… a program could do that in seconds.”
“Then write it”, Lucía replied without looking up.
Marta sat down, opened her laptop, and thought it through: the program should read scores one by one. Since the number of athletes changes every week, Lucía will enter -1 to signal that there are no more scores. The program then computes and prints the average.
One or more integers (scores), one per line, ending with -1.
Print the average of the scores read.
Input:
80
60
100
-1
Output:
80