Chef and digits of a number

Chef has a number D containing only digits 0's and 1's. It can have leading 0's. He wants to make the number to have all the digits same. For that, he will change exactly one digit, i.e. from 0 to 1 or from 1 to 0. If it is possible to make all digits equal (either all 0's or all 1's) by flipping exactly 1 digit then output "Yes", else print "No" (quotes for clarity) Input The first line will co