Numbers and houses anyway
On a town it was decided that all houses of the biggest street should have numbers in order and on plates of the same form.
Therefore everyone went to the local market to buy plates of numbers to put them on their houses.
At the moment the market had only 100 plates of every digit from 0 to 9 (that meaning 100 plates of the digit 0 , 100 plates of the digit 1 and so on until 9). What therefore is the first number made by this digits which can't be written on a house ?
Enter the answer as that number.
For the sake of clarity , the numbers start from 1 not 0 and also they are in the format 1 , 2 and so on not 001 , 002 anyway.
For clarity further suppose the people buy the plates in the order of their houses anyway.