Ritik Jain (SDE 2- R2)
https://drive.google.com/file/d/1t6rgKgxjA_wO_7o6wZ4Wbo4z8R4Mh8r5/view

* one of the best candidates till now
* super in DSA...style of logic building and ease with which he handles different lang syntax is commentable
* good knowledge in prev projects
* able to quickly understand new requirements
* way of explanation is also pretty good
* asking relevant questions, getting clarity on the problem before starting to think of soln, thinking about cases before starting coding..all points hit :heavy_check_mark:

Qns:

1) Flatten deeply nested array
https://leetcode.com/problems/flatten-deeply-nested-array/description/

type MultiDimensionalArray = (number | MultiDimensionalArray)[];

var flat = function (arr:  MultiDimensionalArray, n: number):  MultiDimensionalArray {

    if(n<= 0) {
        return arr;
    }

    const answerArray: MultiDimensionalArray = [];
    for(const i of arr) {
        if(Array.isArray(i)) {
            answerArray.push(...flat(i,n-1 )); 
        } else {
            answerArray.push(i);
        }
    }
    return answerArray;
};


// n/

//[[[[[[[[[1]]]]]]]], 2, 3, 4]

// k+k+k+k...N
// k*n


// n*k ~ O(n)
// n = length of an Array
// k = maximum depth that I needed;

2) Trim a Binary search tree https://leetcode.com/problems/trim-a-binary-search-tree/

/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode() : val(0), left(nullptr), right(nullptr) {}
 *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
 *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
 * };
 */
class Solution {
public:
    TreeNode* trimBST(TreeNode* root, int low, int high) {
        while(root && (root->val < low || root->val > high)) {
            root = root->val < low ? root->right : root->left;
        }

        if(!root) {
            return root;
        }

        TreeNode* node = root;

        // going into left dir
        while(node->left) {
            if(node->left->val < low) {
                node->left = node->left->right;
            } else {
                node = node->left;
            }
        }

        node = root;

        // going into right dir
        while(node->right) {
            if(node->right->val > high) {
                node->right = node->right->left;
            } else {
                node = node->right;
            }
        }

        return root;
    
    }
};

3) explain a use case of event driven system in ur prev role
- explained well how kafka is used for sending email/sms/whatsapp notifications after an order is placed
- very clear on when n why to use

4) coupons module db design

coupons module db design

admin creat coupon
this coupon will apply on product and customer will use to get discount 


order above 500 get discount 10 --> code100


want to show all coupons to cust --->> user

tb_coupons

coupon_id (PK)
coupon_name
max_discount --> 100
percentage --> NULL
description --->
min_order_value. --> 
valid_till
start_by --> start date
max_no_of_coupon_uses ---> 50, null
current_use_count --> 2
created_by
create_date
update_date
delete_date

-------------------
tb_user_coupon uc

id
user_id
coupon_id
created_by
create_date
update_date
delete_date

------------------
tb_product_coupon pc

id
product_id
coupon_id
created_by
create_date
update_date
delete_date

-----------------
tb_orders

order_id
coupon_id
discount_amount ---> 10
currency --> sin, inr
original_price
final_price

 */