program atcoder
    implicit none
    integer(8) :: ans,k,a,b
    logical x
    read*,k,a,b
    x = (b-a)>2
    do while(k>0)
        if(ans>=A .and. x .and. k>1)then
            ans = ans + (b-a)
            k = k-1
        else
            ans = ans + 1
        endif
        k = k-1
    enddo
    write(*,'(I0)')ans
    stop 
contains
end program atcoder