題目:
判斷乙個 9x9 的數獨是否有效。只需要根據以下規則,驗證已經填入的數字是否有效即可。
數字 1-9 在每一行只能出現一次。
數字 1-9 在每一列只能出現一次。
數字 1-9 在每乙個以粗實線分隔的 3x3 宮內只能出現一次。
上圖是乙個部分填充的有效的數獨。
數獨部分空格內已填入了數字,空白格用'.'
表示。
示例1:
輸入:[示例2:["5","3",".",".","7",".",".",".","."],
["6",".",".","1","9","5",".",".","."],
[".","9","8",".",".",".",".","6","."],
["8",".",".",".","6",".",".",".","3"],
["4",".",".","8",".","3",".",".","1"],
["7",".",".",".","2",".",".",".","6"],
[".","6",".",".",".",".","2","8","."],
[".",".",".","4","1","9",".",".","5"],
[".",".",".",".","8",".",".","7","9"]
]輸出:true
輸入:[分析:1.判斷值存不存在可以使用hashset;["8","3",".",".","7",".",".",".","."],
["6",".",".","1","9","5",".",".","."],
[".","9","8",".",".",".",".","6","."],
["8",".",".",".","6",".",".",".","3"],
["4",".",".","8",".","3",".",".","1"],
["7",".",".",".","2",".",".",".","6"],
[".","6",".",".",".",".","2","8","."],
[".",".",".","4","1","9",".",".","5"],
[".",".",".",".","8",".",".","7","9"]
]輸出:false
解釋: 除了第一行的第乙個數字從 5 改為 8以外,空格內其他數字均與 示例1 相同。
但由於位於左上角的 3x3 宮內有兩個 8 存在, 因此這個數獨是無效的。
2.每行、每列、每3x3 宮可以單獨放在乙個hashset中判斷數值是否重複;
**:
publicboolean isvalidsudoku(char
board)
for (int i=0;i<9;i++)
if(row[i].contains(board[i][j]))
if(column[j].contains(board[i][j]))
int boxindex = i/3*3 + j/3;
if(box[boxindex].contains(board[i][j]))
row[i].add(board[i][j]);
column[j].add(board[i][j]);
box[boxindex].add(board[i][j]);}}
return
true
; }
Leetcode題庫 36 有效的數獨
author zzq software pycharm file leetcode36 isvalidsudoku.py time 2018 11 19 19 27 要求 判斷乙個 9x9 的數獨是否有效。只需要根據以下規則,驗證已經填入的數字是否有效即可。數字 1 9 在每一行只能出現一次。數字 ...
LeetCode 36 有效的數獨
題目鏈結 題目描述 判斷乙個 9x9 的數獨是否有效。只需要根據以下規則,驗證已經填入的數字是否有效即可。數字 1 9 在每一行只能出現一次。數字 1 9 在每一列只能出現一次。數字 1 9 在每乙個以粗實線分隔的 3x3 宮內只能出現一次。上圖是乙個部分填充的有效的數獨。數獨部分空格內已填入了數字...
LeetCode 36 有效的數獨
public boolean isvalidsudoku char board 檢查行 if isparticallyvalid board,i,i,0,8 檢查塊 for int i 0 i 3 i return true 把要檢查的值存入到set中,每次向set中新增值的時候,如果失敗則證明該值...