Calculate n + nn + nnn + … + n(m times) in Python

The program is to find a mathematical series, where we need to accept the value of n and m. n is the base number and m is the number of times till which the series run.


Input : 2 + 22 + 222 + 2222 + 22222 
Output : 24690

Input : 12 + 1212 + 121212
Output : 122436

We first convert the numbers into string format and concatenate them regularly. Later, we convert them back to integer and add them upto mth term. as shown in the following program.





# Python program to sum the given series
# Returns sum of n + nn + nnn + .... (m times)
def Series(n, m):
    # Converting the number to string
    str_n = str(n)
    # Initializing result as number and string
    sums = n
    sum_str = str(n)
    # Adding remaining terms
    for i in range(1, m):
        # Concatenating the string making n, nn, nnn...
        sum_str = sum_str + str_n
        # Before adding converting back to integer
        sums = sums + int(sum_str)
    return sums
# Driver Code
n = 2
m = 5
total = Series(n, m)




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