POTD-Floor in BST.cpp

class Solution{

public:
    int floor(Node* root, int x) {
       int res = -1;
    while (root != nullptr) {
        if (root->data == x) {
            return root->data;
        }
        if (root->data > x) {
            root = root->left;
        } else {
            res = root->data;
            root = root->right;
        }
    }
    return res;
    }
};