N,K=map(int,input().split())
K-=1
if N==1:
    ans=K
elif N==2:
    if K==0:
        ans=1
    else:
        ans=0
else:
    if K==N-1:
        l,r=1,N-1
    else:
        l,r=K+1,N-1
    while r-l>=2:
        m=(l+r-1)//2
        if m+1<r:
            l=m+1
        else:
            r=m
    ans=l
print(ans+1)