#Write a function sumDivisor that has one parameter positive integer. The 
#function finds and prints the sum of all divisors of the parameter 
#Write a program that reads a sequence of positive 
#integers. First negative or zero terminates the input. For each number, 
#program uses function sumDivisor to find the sum of the divisors 


#Discussion: function sumDivisor. Example: parameter 15, function returns 
#1+3+5+15 
#1 is a divisor of 15: 15%1 equals 0
#3 is a divisor of 15: 15%3 equals 0
#5 is a divisor of 15: 15%5 equals 0
#15 is a divisor of 15: 15%15 equals 0

#d is a divisor of num, if num%d equals 0

#In main: sentinel-controlled repetition

def sumDivisor(num):
	sum=0
	counter=1 #0 is not a valid divisor
	while(counter<=num):
		if(num%counter==0):
			sum=sum+counter
		counter=counter+1

	return sum

def main():
	num=int(input("enter positive number "))
	while(num>0):
		print(sumDivisor(num))
		num=int(input("enter positive number "))
main()

#While input is positive the loop continue to execute
#NO COUNTER to control loop execution

#Tracing: num = 6
#counter=1 1<=6 True 6%1==0 True, sum=0+1=1, counter=2
#counter=2 2<=6 True 6%2==0 True, sum=1+2=3, counter=3
#counter=3 3<=6 True 6%3==0 True, sum=3+3=6, counter=4
#counter=4 4<=6 True 6%4==0 False, counter=5
#counter=5 5<=6 True 6%5==0 False, counter=6
#counter=6 6<=6 True 6%6==0 True, sum=6+6=12, counter=7
#counter=7 7<=6 False loop is terminated