Add LeetCode solution 1536

Author: eselyavka

practice/leetcode/solutions_01500/solution_01536.py

@@ -0,0 +1,57 @@
+#!/usr/bin/env python3
+
+"""LeetCode solution 01536."""
+
+import unittest
+
+
+class Solution(object):
+    def minSwaps(self, grid):
+        """
+        :type grid: List[List[int]]
+        :rtype: int
+        """
+        n = len(grid)
+        trailing_zeros = [0] * n
+
+        for i in range(n):
+            tail_zeros = 0
+            for j in range(n - 1, -1, -1):
+                if grid[i][j]:
+                    break
+                tail_zeros += 1
+
+            trailing_zeros[i] = tail_zeros
+
+        answer = 0
+        for i in range(n - 1):
+            required = n - i - 1
+
+            index = -1
+            for j in range(i, n):
+                if trailing_zeros[j] >= required:
+                    index = j
+                    break
+
+            if index == -1:
+                return -1
+
+            while index > i:
+                answer += 1
+                trailing_zeros[index - 1], trailing_zeros[index] = (
+                    trailing_zeros[index],
+                    trailing_zeros[index - 1],
+                )
+                index -= 1
+
+        return answer
+
+
+class TestSolution(unittest.TestCase):
+    def test_minSwaps(self):
+        solution = Solution()
+        self.assertEqual(solution.minSwaps([[0, 0, 1], [1, 1, 0], [1, 0, 0]]), 3)
+
+
+if __name__ == '__main__':
+    unittest.main()