python - how to stop a for loop

Question

I'm writing a code to determine if every element in my nxn list is the same. i.e. [[0,0],[0,0]] returns true but [[0,1],[0,0]] will return false. I was thinking of writing a code that stops immediately when it finds an element that is not the same as the first element. i.e:

n=L[0][0]
m=len(A)
for i in range(m):
 for j in range(m):
   if
    L[i][j]==n: -continue the loop-
   else: -stop the loop-

I would like to stop this loop if L[i][j]!==n and return false. otherwise return true. How would I go about implementing this?

Answer 1

Use break and continue to do this. Breaking nested loops can be done in Python using the following:

for a in range(...):
   for b in range(..):
      if some condition:
         # break the inner loop
         break
   else:
      # will be called if the previous loop did not end with a `break` 
      continue
   # but here we end up right after breaking the inner loop, so we can
   # simply break the outer loop as well
   break

Another way is to wrap everything in a function and use return to escape from the loop.