Alice:90, Bob:70, Chris:80

Alice
Bob
80.0

d = {}
for item in input().split(','):
    k, v = item.strip().split(':')
    d[k.strip()] = int(v.strip())
best = max(d, key=d.get)
worst = min(d, key=d.get)
avg = round(sum(d.values()) / len(d), 1)
print(best)
print(worst)
print(avg)