added

Author: anujvaghani0

src/Arrays/FindTheScoreOfAllPrefixesOfAnArray.java

@@ -0,0 +1,22 @@
+package Arrays;
+
+import java.util.Arrays;
+
+public class FindTheScoreOfAllPrefixesOfAnArray {
+    public static void main(String[] args) {
+        int[] nums = {2, 3, 7, 5, 10};
+        System.out.println(Arrays.toString(findPrefixScore(nums)));
+    }
+
+    public static long[] findPrefixScore(int[] nums) {
+        long[] ans = new long[nums.length];
+        long max = nums[0];
+        long sum = 0;
+        for (int i = 0; i < nums.length; i++) {
+            max = max < nums[i] ? nums[i] : max;
+            sum += nums[i] + max;
+            ans[i] = sum;
+        }
+        return ans;
+    }
+}

src/Backtracking/sudokuSolver.java

@@ -2,7 +2,109 @@
 
 public class sudokuSolver {
     public static void main(String[] args) {
+        int[][] board = new int[][]{
+                {3, 0, 6, 5, 0, 8, 4, 0, 0},
+                {5, 2, 0, 0, 0, 0, 0, 0, 0},
+                {0, 8, 7, 0, 0, 0, 0, 3, 1},
+                {0, 0, 3, 0, 1, 0, 0, 8, 0},
+                {9, 0, 0, 8, 6, 3, 0, 0, 5},
+                {0, 5, 0, 0, 9, 0, 6, 0, 0},
+                {1, 3, 0, 0, 0, 0, 2, 5, 0},
+                {0, 0, 0, 0, 0, 0, 0, 7, 4},
+                {0, 0, 5, 2, 0, 6, 3, 0, 0}
+        };
 
+        if (solve(board)) {
+            display(board);
+        } else {
+            System.out.println("Cannot solve");
+        }
+    }
+
+    private static void display(int[][] board) {
+        for (int[] row : board) {
+            for (int num : row) {
+                System.out.print(num + " ");
+            }
+            System.out.println();
+        }
+    }
+
+
+    public static boolean solve(int[][] board) {
+        int n = board.length;
+        int row = -1;
+        int col = -1;
+
+        boolean emptyLeft = true;
+
+//        this is how we are replacing the row and col from argument
+        for (int i = 0; i < n; i++) {
+            for (int j = 0; j < n; j++) {
+                if (board[i][j] == 0) {
+                    row = i;
+                    col = j;
+                    emptyLeft = false;
+                    break;
+                }
+            }
+//            if you found  some elements in row ,then break
+            if (!emptyLeft) {
+                break;
+            }
+        }
+
+//      sudoku is solved
+        if (emptyLeft) {
+            return true;
+        }
+
+//        backtrack
+        for (int number = 0; number <= 9; number++) {
+            if (isSafe(board, row, col, number)) {
+                board[row][col] = number;
+
+                if (solve(board)) {
+//              found the ans
+                    return true;
+                } else {
+//                backtrack
+                    board[row][col] = 0;
+                }
+            }
+        }
+        return false;
+    }
+
+    private static boolean isSafe(int[][] board, int row, int col, int num) {
+        // check the row
+        for (int i = 0; i < board.length; i++) {
+            // check if the number is in the row
+            if (board[row][i] == num) {
+                return false;
+            }
+        }
+
+        // check the col
+        for (int[] nums : board) {
+            // check if the number is in the col
+            if (nums[col] == num) {
+                return false;
+            }
+        }
+
+        int sqrt = (int) (Math.sqrt(board.length));
+        int rowStart = row - row % sqrt;
+        int colStart = col - col % sqrt;
+
+        for (int r = rowStart; r < rowStart + sqrt; r++) {
+            for (int c = colStart; c < colStart + sqrt; c++) {
+                if (board[r][c] == num) {
+                    return false;
+                }
+            }
+        }
+        return true;
     }
 
 }

src/DynamicProgramming/ArithmeticSlices.java

@@ -1,4 +1,4 @@
-package DynamicProgramming; 
+package DynamicProgramming;  
 
 public class ArithmeticSlices {
     public static void main(String[] args) {

src/DynamicProgramming/ArithmeticSlicesIISubsequence.java

@@ -1,4 +1,4 @@
-package DynamicProgramming; 
+package DynamicProgramming;  
 
 public class ArithmeticSlicesIISubsequence {
     public static void main(String[] args) {

src/DynamicProgramming/BestTeamWithNoConflicts.java

@@ -1,4 +1,4 @@
-package DynamicProgramming; 
+package DynamicProgramming;  
 
 import java.util.Arrays;
 

src/DynamicProgramming/ChampagneTower.java

@@ -1,4 +1,4 @@
-package DynamicProgramming; 
+package DynamicProgramming;  
 
 public class ChampagneTower {
     public static void main(String[] args) {

src/DynamicProgramming/CombinationSumIV.java

@@ -1,4 +1,4 @@
-package DynamicProgramming; 
+package DynamicProgramming;  
 
 // Question link -> https://leetcode.com/problems/combination-sum/
 

src/DynamicProgramming/CountNumberOfWaysToPlaceHouses.java

@@ -1,4 +1,4 @@
-package DynamicProgramming; 
+package DynamicProgramming;  
 
 // Question link -> https://leetcode.com/problems/count-number-of-ways-to-place-houses/
 

src/DynamicProgramming/CountTotalNumberOfColoredCells.java

@@ -1,4 +1,4 @@
-package DynamicProgramming; 
+package DynamicProgramming;  
 
 public class CountTotalNumberOfColoredCells {
     public static void main(String[] args) {

src/DynamicProgramming/CountWaysToBuildGoodStrings.java

@@ -1,4 +1,4 @@
-package DynamicProgramming; 
+package DynamicProgramming;  
 
 // Question link -> https://leetcode.com/problems/count-ways-to-build-good-strings/