Word Search

Author: alisamad1

Leetcode_Practice_Questions/LC_1219.cpp

@@ -3,24 +3,26 @@ int recursion(int i , int j, vector<vector<int> >&grid){
     if(i<0 || j<0 || i == grid.size() || j == grid[0].size() || grid[i][j] == 0){
         return 0;
     }
-    int current = grid[i][j];
-    grid[i][j] = 0;
-    int ans = current;
-    int ans1 = 0;
-    ans1 = max(ans1,recursion(i-1,j,grid));
-    ans1 = max(ans1,recursion(i+1,j,grid));
-    ans1 = max(ans1, recursion(i,j+1,grid));
-    ans1 = max(ans1, recursion(i,j-1,grid));
-    ans+=ans1;
-    grid[i][j] = current;
-    return ans;
+
+    int originalGold = grid[r][c];
+    grid[r][c] = 0; // Mark as visited by taking the gold
+
+    // Explore all 4 directions and find the path with the maximum gold
+    int maxGoldFromNeighbors = 0;
+    maxGoldFromNeighbors = max(maxGoldFromNeighbors, dfs(r + 1, c, grid));
+    maxGoldFromNeighbors = max(maxGoldFromNeighbors, dfs(r - 1, c, grid));
+    maxGoldFromNeighbors = max(maxGoldFromNeighbors, dfs(r, c + 1, grid));
+    maxGoldFromNeighbors = max(maxGoldFromNeighbors, dfs(r, c - 1, grid));
+
+    grid[r][c] = originalGold; // Backtrack: put the gold back for other paths
+    return originalGold + maxGoldFromNeighbors;
 }
 int getMaximumGold(vector<vector<int>>& grid) {
     int ans = 0;
     for(int i = 0; i<grid.size(); i++){
         for(int j = 0; j<grid[0].size();j++){
             if(grid[i][j]!= 0){
-                ans = max(ans,recursion(i,j,grid));
+                ans = max(ans, dfs(i, j, grid));
             }
         }
     }

Leetcode_Practice_Questions/LC_79.cpp

@@ -0,0 +1,52 @@
+#include<iostream>
+#include<vector>
+#include<string>
+using namespace std;
+class Solution{
+public:
+    int m; 
+    int n;
+    vector<vector<char>> board;
+    string word; 
+    bool backtrack(int i, int j ,int k){
+        if(k == word.length()){
+            return true;
+        }
+        if(i < 0 || i >= m || j < 0 || j >= n || board[i][j] != word[k]){
+            return false;
+        }
+        char temp = board[i][j];
+        board[i][j] = '\0';
+        bool found = backtrack(i + 1, j, k + 1) || backtrack(i - 1, j , k + 1) || backtrack(i, j + 1,  k + 1) || backtrack(i , j - 1, k + 1);
+        board[i][j] = temp;
+        return found;
+    }
+    bool exist(vector<vector<char>> board, string word){
+        this-> m = board.size();
+        this-> n = board[0].size(); 
+        for(int i = 0 ; i < m; i++){
+            for(int j = 0; j < n; j++){
+                if(backtrack(i , j , 0)){
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
+};
+int main(){
+    vector<vector<char>> board = {
+        {'A', 'B', 'C', 'E'},
+        {'S', 'F', 'C', 'S'},
+        {'A', 'D', 'E', 'E'}
+    };
+    Solution sol;
+    string word = "ABCCED";
+    if(sol.exist(board, word)){
+        cout << "The elements are present in the board" << endl;
+    }
+    else{
+        cout << "The element are not present in the board" << endl;
+    }
+    return 0;
+}