program main
	implicit none
    character(10)::s
    read(*,*)s
    if(len_trim(s)<=3)then
    	write(*,*)'No'
    else
    	if(s(1:4)=='YAKI')then
        	write(*,*)'Yes'
        else
        	write(*,*)'No'
        end if
    end if
    stop
    
end program main