Feedback for DIFFCONSEC problem

Problem Link: DIFFCONSEC Problem - CodeChef

This problem should be tested for 111 as the binary which should give the output 1 because to satisfy the given conditions we can convert it to 101 by doing operation one time but the codes submitted are giving 2 as all the codes are counting pair of same numbers.
if I am getting something wrong, then please correct me which lead is missed by me