def maximumDifference(self, nums: List[int]) -> int:
minVal = float('inf')
diff = -1
for n in nums:
if n < minVal:
minVal = min(n,minVal)
else:
currDiff = n - minVal
if currDiff > 0:
diff = max(diff, currDiff)
return diff
trick
- track the smallest number, and if the number is STRICTLY greater than the smallest num then we get the difference