Instructions

BeautifulBinary

String

Alicehasabinarystring, ,oflength .Shethinksabinarystringisbeautifulifandonlyifitdoesn'tcontain

thesubstring .

Inonestep,Alicecanchangea toa (orvice-versa).Countandprinttheminimumnumberofsteps

neededtomakeAliceseethestringasbeautiful.

InputFormat

Thefirstlinecontainsaninteger, (thelengthofbinarystring ).

0101010

SampleOutput0

SampleInput1

01100

SampleOutput1

SampleInput2

SampleCase0:

Inthissample,

Becausewewereabletomakethestringbeautifulbychanging characters( and ),weprint .

SampleCase1:

Inthissample

Thesubstring doesnotoccurin ,sothestringisalreadybeautifulandweprint .