title: How can I generate a random point (x, y) 10 steps apart from y0(a, b) in xy-plane?
body: <p>I have generated a random  point named <code>y0=(a,b)</code> in xy-plane , How can I generate another random point <code>(x,y)</code> 10 steps apart from <code>y0</code>? </p>
  
  <p>note: by 10 steps apart from the firt point I don't mean the Euclidean distance. I mean the number of steps on lattice between the two point (a,b) and (x,y) which is given by |x-a|+|y-b|=10</p>
  
  <p>My attempt(sometimes gives wrong result).</p>
  
  <pre><code>import random
  y0=(random.randint(0,50),random.randint(0,50))# here I generated the first point.
  y=random.randint(0,50)
  
  # I used the formula  |x-a|+|y-b|=10.
  x=(10 -abs(y-y0[1]))+y0[0]  or x=-(10 -abs(y-y0[1]))+y0[0]
  
  x0=(x,y)
  </code></pre>