3

 
 
  
  # 3. Write a Program to Count Digits in a Number using while loop 
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num = int(input(“Enter value of n: ”))

if num < 0:
   print("Enter a positive number")
else:
   sum = 0
   # use while loop to iterate until zero
   while(num > 0):
       sum += num
       num -= 1
   print("The sum is", sum)


OUTPUT
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