Create monotone-increasing-digits.py

jcliu0428 · Dec 3, 2017 · 7dbc167 · 7dbc167
1 parent 3eb4c3f
commit 7dbc167
Showing 1 changed file with 18 additions and 0 deletions.
diff --git a/Python/monotone-increasing-digits.py b/Python/monotone-increasing-digits.py
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+# Time:  O(logn) = O(1)
+# Space: O(logn) = O(1)
+
+class Solution(object):
+    def monotoneIncreasingDigits(self, N):
+        """
+        :type N: int
+        :rtype: int
+        """
+        nums = map(int, list(str(N)))
+        leftmost_inverted_idx = len(nums)
+        for i in reversed(xrange(1, len(nums))):
+            if nums[i-1] > nums[i]:
+                leftmost_inverted_idx = i
+                nums[i-1] -= 1
+        for i in xrange(leftmost_inverted_idx, len(nums)):
+            nums[i] = 9
+        return int("".join(map(str, nums)))