'''
Created on Sep 24, 2012

@author: ola
'''
import math

def inside(x,y,xc,yc,rad):
    '''
    return True if and only if (x,y) inside circle (xc,yc) radius rad
    '''
    xdiff = x-xc
    ydiff = y-yc
    dist = math.sqrt(xdiff*xdiff + ydiff*ydiff)
    #return dist < rad:
    if dist < rad: 
        return True
    else:
        return False
  

def leastBorders(x,y,r,x1,y1,x2,y2):
    s = 0
    for index in range(0,len(x)):
        xc = x[index]
        yc = y[index]
        rad = r[index]
        if inside(x1,y1,xc,yc,rad) and not inside(x2,y2,xc,yc,rad):
            s = s + 1
       
    return s