```
class Solution:
def coverPoints(self, A, B):
x1 = A[0]
y1 = B[0]
res = 0
for i in range(1,len(A)):
x2,y2 = A[i],B[i]
diff1 = abs(x1-x2)
diff2 = abs(y1-y2)
res += diff1 + diff2
if x1!=x2 and y1!=y2:
res-=min(diff1,diff2)
x1,y1 = x2,y2
return res
```

# Python 3 O(n) solution

**ashish-karkera_802**