#Write a program that reads a sequence of non-zero integers. First zero 
#value will terminate the input. The program finds and prints the number 
#of inputs, their sum and average. 

count=0
sum=0
#we have to read first input BEFORE the loop
num=int(input("enter non zero, first zero stops the input "))
while(num!=0):
	count=count+1
	sum=sum+num
	num=int(input("enter non zero, first zero stops the input "))
if(count>0):
	print("there are",count,"inputs")
	print("their sum is",sum)
	print("their average is",sum/count)
else:
	print("empty input")

#Tracing program for the following input: 3 -2 7 8 0 
#count=0 sum=0 num=3
#loop starts
#loop condition: num!=0, num is 3 now, 3!=0 is True,loop will be executed
#loop will be executed
#loop body: count=count+1=0+1=1, sum=sum+num=0+3=3, next input will be read, 
#num=-2
#loop condition: num!=0, num is -2, -2!=0 is True, loop will be executed
#loop body: count=count+1=1+1=2, sum=3+(-2)=1, next input, num=7
#loop condition: num!=0, num is 7, 7!=0 is True, loop will be executed
#loop body: count=count+1=2+1=3, sum=1+7=8, next num=8 
#loop condition: num!=0, num is 8, 8!=0 is True, loop will be executed
#loop body: count=count+1=3+1=4, sum=8+8=16, num=0
#loop condition: num!=0, num is 0, 0!=0 is False and loop will be terminated

#After loop is done, count=4, sum=16
#count>0, True and if statement will be executed
#final output:
#there are 4 inputs
#their sum is 16
#their average is 4.0