Month: February 2025

vector<vector<int>> levelOrder(Node *root) {
        // Your code here
        vector<vector<int>> ans;
        if(root == NULL) return ans;
        queue<Node*> q;
        q.push(root);
        while(!q.empty()) {
            vector<int> res;
            int len = q.size();
            for(int i=0; i<len; i++) {
                Node *cur = q.front();
                q.pop();
                res.push_back(cur->data);
                if(cur->left) q.push(cur->left);
                if(cur->right) q.push(cur->right);
            }
            ans.push_back(res);
        }
        return ans;
    }

bool solve(vector<vector<char>>& mat, string& word, int i, int j, int widx) {
        int wlen = word.length();
        int n = mat.size();
        int m = mat[0].size();
        //base case
        if(widx == wlen) return true;
        if(i<0 || j<0 || i>=n || j>=m) return false;
        //recursive case
        if(mat[i][j] == word[widx]) {
            bool res = false;
            char tmp = mat[i][j];
            mat[i][j] = '_';
            if(solve(mat, word, i-1, j, widx+1) || solve(mat, word, i+1, j, widx+1) ||
                solve(mat, word, i, j+1, widx+1) || solve(mat, word, i, j-1, widx+1)) 
                    res = true;
            mat[i][j] = tmp;
            return res;
        }
        return false;
    }
    bool isWordExist(vector<vector<char>>& mat, string& word) {
        // Code here
        int n = mat.size();
        int m = mat[0].size();
        int wlen = word.length();
        for(int i=0;i<n; i++) {
            for(int j=0; j<m; j++) {
                if(solve(mat, word, i, j, 0)) return true;
            }
        }
        return false;
    }