[Tutor] Occurrence of number 2 in a range from 1 to 100

[Steven D'Aprano]

On Sun, Dec 01, 2013 at 02:57:33PM +0530, Reuben wrote:
> I mean occurrence of 2 from numbers 1 to 100.  The number could be the
> first digit or second digit in a two digit number..for e.g. In number 21 it
> appears as first digit. For number 92 it appears as second digit

The most efficient way is to use a bit of reasoning:

2, 12, 20 through 29, then 32, 42, 52 etc.

But if you have to do it computationally:

for i in range(1, 101):
    print "2" in str(i)



-- 
Steven