37_Suduko solver_CPP

C++/3. Suduko Solver.cpp

@@ -0,0 +1,39 @@
+// Question Link --> https://leetcode.com/problems/suduko-solver/
+
+
+
+class Solution {
+public:
+    bool isItSafe(vector<vector<char>>& board , int n , int row , int col , char num){
+        for(int pos=0;pos<n;pos++){
+            if(board[row][pos]==num) return false;
+            if(board[pos][col]==num) return false;
+            if(board[(row/3)*3 + pos/3][(col/3)*3 + pos%3]==num) return false;
+        }
+        return true;
+    }
+
+    bool returnSolvedSuduko(vector<vector<char>>& board){
+        int n = board.size();
+        for(int row=0;row<n;row++){
+            for(int col=0;col<n;col++){
+                if(board[row][col]=='.'){
+                    for(char num='1';num<='9';num++){
+                        if(isItSafe(board,n,row,col,num)){
+                            board[row][col]=num;
+                            if(returnSolvedSuduko(board))
+                                return true;
+                            board[row][col]='.';
+                        }
+                    }
+                    return false;
+                }
+            }
+        }
+        return true;
+    }
+    void solveSudoku(vector<vector<char>>& board) {
+        returnSolvedSuduko(board);
+        return;
+    }
+};