k=0
s=0
f=0
for i in range(100):
a=int(input("ddd "))
if a==0:
break
if a>99 and a<1000:
k=k+1
s=s+a
else:
f=f+1
if f==0:
print("NO")
else:
print(s/k)
школа 1747
k=0
s=0
f=0
for i in range(100):
a=int(input("ddd "))
if a==0:
break
if a>99 and a<1000:
k=k+1
s=s+a
else:
f=f+1
if f==0:
print("NO")
else:
print(s/k)