Python Program to Count the Number of Digits Present In a Number

Example 1: Count Number of Digits in an Integer using while loop

num = 3452
count = 0

while num != 0:
    num //= 10
    count += 1

print("Number of digits: " + str(count))

Output

Number of digits: 4

In this program, the while loop is iterated until the test expression num != 0 is evaluated to 0 (false).

1. After the first iteration,
   num
   will be divided by 10 and its value will be 345. Then, the
   count
   is incremented to 1.
2. After the second iteration, the value of
   num
   will be 34 and the
   count
   is incremented to 2.
3. After the third iteration, the value of
   num
   will be 3 and the
   count
   is incremented to 3.
4. After the fourth iteration, the value of
   num
   will be 0 and the
   count
   is incremented to 4.
5. Then the test expression is evaluated to false and the loop terminates.

Example 2: Using inbuilt methods

num = 123456
print(len(str(num)))

Output

6

In the above example, we first convert the integer value into string by using str(). Then, we find the length of the string using len().