Write a program to find all the possible solutions of a Sudoku.
Input begins with a number , followed by Sudokus. Every Sudoku consists of 81 numbers between zero and nine, plus the characters shown in the examples. A zero indicates an unknown value. Except for zeros, there are no repeated numbers in any row, nor in any column, nor in any of the nine squares.
For every Sudoku, print all the possible solutions in lexicographical
order, each one followed by an empty line. Print
“no solution” if there is no solution. Print a line with 30
asterisks after the output for every Sudoku.
The data tests are chosen so that a backtracking program that simply fills the rows from top to bottom and from left to right will be fast enough.
Input
3 0 8 0 | 0 5 9 | 0 0 0 7 0 3 | 0 0 0 | 0 0 0 6 4 9 | 7 0 0 | 0 0 0 ------+-------+------ 0 6 4 | 0 0 3 | 0 0 5 0 0 7 | 0 0 0 | 6 0 0 8 0 0 | 6 0 0 | 0 4 0 ------+-------+------ 0 0 0 | 0 0 7 | 3 2 8 0 0 0 | 0 0 0 | 1 0 7 0 0 0 | 8 9 0 | 0 0 0 1 2 3 | 4 5 6 | 7 8 9 4 5 6 | 0 0 0 | 0 0 0 7 8 9 | 0 0 0 | 0 6 0 ------+-------+------ 2 0 0 | 1 0 0 | 0 0 0 5 0 0 | 0 2 0 | 8 0 0 8 0 1 | 5 0 3 | 9 0 0 ------+-------+------ 3 0 0 | 0 6 0 | 1 9 8 6 0 0 | 0 0 0 | 0 2 7 9 7 5 | 8 0 0 | 0 0 3 1 2 3 | 4 5 6 | 7 8 9 9 8 7 | 3 2 1 | 6 5 4 4 5 6 | 7 8 9 | 1 2 3 ------+-------+------ 3 9 2 | 8 4 5 | 0 0 0 0 0 0 | 0 0 0 | 0 0 0 0 0 0 | 0 0 0 | 0 0 0 ------+-------+------ 0 0 0 | 0 0 0 | 0 0 0 0 0 0 | 0 0 0 | 0 0 0 0 0 0 | 0 0 0 | 0 0 0
Output
1 8 2 | 3 5 9 | 4 7 6 7 5 3 | 2 6 4 | 9 8 1 6 4 9 | 7 1 8 | 2 5 3 ------+-------+------ 2 6 4 | 9 7 3 | 8 1 5 9 1 7 | 4 8 5 | 6 3 2 8 3 5 | 6 2 1 | 7 4 9 ------+-------+------ 5 9 6 | 1 4 7 | 3 2 8 4 2 8 | 5 3 6 | 1 9 7 3 7 1 | 8 9 2 | 5 6 4 ****************************** 1 2 3 | 4 5 6 | 7 8 9 4 5 6 | 9 7 8 | 2 3 1 7 8 9 | 2 3 1 | 4 6 5 ------+-------+------ 2 9 4 | 1 8 7 | 3 5 6 5 3 7 | 6 2 9 | 8 1 4 8 6 1 | 5 4 3 | 9 7 2 ------+-------+------ 3 4 2 | 7 6 5 | 1 9 8 6 1 8 | 3 9 4 | 5 2 7 9 7 5 | 8 1 2 | 6 4 3 1 2 3 | 4 5 6 | 7 8 9 4 5 6 | 9 8 7 | 2 3 1 7 8 9 | 2 3 1 | 4 6 5 ------+-------+------ 2 9 4 | 1 7 8 | 3 5 6 5 3 7 | 6 2 9 | 8 1 4 8 6 1 | 5 4 3 | 9 7 2 ------+-------+------ 3 4 2 | 7 6 5 | 1 9 8 6 1 8 | 3 9 4 | 5 2 7 9 7 5 | 8 1 2 | 6 4 3 ****************************** no solution ******************************