Create special-positions-in-a-binary-matrix.py

Author: kamyu104

Python/special-positions-in-a-binary-matrix.py

@@ -0,0 +1,21 @@
+# Time:  O(n^2)
+# Space: O(n)
+
+class Solution(object):
+    def numSpecial(self, mat):
+        """
+        :type mat: List[List[int]]
+        :rtype: int
+        """
+        rows, cols = [0]*len(mat), [0]*len(mat[0])
+        for i in xrange(len(rows)):
+            for j in xrange(len(cols)):
+                if mat[i][j]:
+                    rows[i] += 1
+                    cols[j] += 1
+        result = 0
+        for i in xrange(len(rows)):
+            for j in xrange(len(cols)):
+                if mat[i][j] == rows[i] == cols[j] == 1:
+                    result += 1
+        return result