program main
    use,intrinsic :: iso_fortran_env
    implicit none
    integer(int32):: n,n2,s,ns,v,i,j,dx,dy
    integer(int32),parameter:: inf = 1001001001
    integer(int32):: x0,y0
    integer(int32), allocatable:: x(:),y(:)
    real(real64), allocatable:: dp(:,:),w(:)
    real(real64):: dt,ans,nw

    read*, x0,y0
    read*, n
    allocate(x(n),y(n),w(n))
    read*, (x(i),y(i),w(i), i=1,n)
    x(:)=x(:)-x0
    y(:)=y(:)-y0
    n2 = lshift(1,n)-1
    allocate(dp(n,0:n2), source=dble(inf))
    dp(1,0) = 0d0

    nw = sum(w)
    dt = f(nw)
    do i=1,n
        ns = ibset(0,i-1)
        dx = abs(x(i))
        dy = abs(y(i))
        dp(i,0) = dble(dx+dy)*dt
    end do

    do s=0,n2
        nw=0
        do i=1,n
            if (.not.btest(s,i-1)) nw=nw+w(i)
        end do
        dt = f(nw)
        do v=1,n
            do i=1,n
                ns = ibset(s,i-1)
                if (ns==s) cycle
                dx = abs(x(v)-x(i))
                dy = abs(y(v)-y(i))
                dp(i,ns) = min(dp(i,ns), dp(v,s)+dble(dx+dy)*dt)
            end do
        end do
    end do
    ans=inf
    dt = f(0d0)
    do v=1,n
        dx = abs(x(v))
        dy = abs(y(v))
        ans=min(ans,dp(v,n2)+dble(dx+dy)*dt)
    end do
    print*, ans+dble(sum(w))
contains
    function f(w)
        real(real64):: w,f
        f = (w+100d0)/120d0
    end function
end program main