update 36 Valid Sudoku

Author: selfboot

HashTable/36_ValidSudoku.cpp

@@ -0,0 +1,34 @@
+/*
+ * @Author: [email protected]
+ * @Last Modified time: 2016-07-13 21:09:57
+ */
+
+class Solution
+{
+public:
+    /*
+    According to:
+    https://discuss.leetcode.com/topic/8241/my-short-solution-by-c-o-n2
+    */
+    bool isValidSudoku(vector<vector<char> > &board)
+    {
+        int row[9][9] = {0}, col[9][9] = {0}, panel[9][9] = {0};
+
+        for(int i = 0; i < board.size(); ++i)
+            for(int j = 0; j < board[i].size(); ++j)
+                if(board[i][j] != '.')
+                {
+                    int num = board[i][j] - '0' - 1, k = i / 3 * 3 + j / 3;
+                    if(row[i][num] || col[j][num] || panel[k][num])
+                        return false;
+                    row[i][num] = col[j][num] = panel[k][num] = 1;
+                }
+
+        return true;
+    }
+};
+
+/*
+["..4...63.",".........","5......9.","...56....","4.3.....1","...7.....","...5.....",".........","........."]
+[".87654321","2........","3........","4........","5........","6........","7........","8........","9........"]
+*/

HashTable/36_ValidSudoku.py

@@ -0,0 +1,40 @@
+#! /usr/bin/env python
+# -*- coding: utf-8 -*-
+
+
+class Solution(object):
+    def isValidSudoku(self, board):
+        # check for rows
+        for row in board:
+            row_hash = {}
+            for c in row:
+                if c != "." and c in row_hash:
+                    return False
+                row_hash[c] = 1
+
+        # check for cols
+        for i in range(9):
+            col_hash = {}
+            for row in board:
+                if row[i] != "." and row[i] in col_hash:
+                    return False
+                col_hash[row[i]] = 1
+
+        # check for panel
+        for i in range(0, 9, 3):
+            for j in range(0, 9, 3):
+                count = 0
+                panel_hash = {}
+                while(count < 9):
+                    c = board[i + count // 3][j + count % 3]
+                    count += 1
+                    if c != "." and c in panel_hash:
+                        return False
+                    panel_hash[c] = 1
+
+        return True
+
+"""
+["..4...63.",".........","5......9.","...56....","4.3.....1","...7.....","...5.....",".........","........."]
+[".87654321","2........","3........","4........","5........","6........","7........","8........","9........"]
+"""

README.md

@@ -88,6 +88,7 @@
 * 001. [Two Sum](HashTable/01_TwoSum.py)
 * 003. [Longest Substring Without Repeating Characters](HashTable/03_LongestSubstringWithoutRepeatingCharacters.py)
 * 018. `4Sum`
+* 036. [Valid Sudoku](HashTable/36_ValidSudoku.py)
 * 049. [Group Anagrams](HashTable/49_GroupAnagrams.py)
 * 128. [Longest Consecutive Sequence](HashTable/128_LongestConsecutiveSequence.py)
 * 146. [LRU Cache](HashTable/146_LRUCache_pythonic.py)