Fullstack Developer

First, I sorted the array in ascending order to apply the two-pointer technique efficiently.

I initialized two variables (pointers): one at the start of the array (left) and one at the end of the array (right).

I calculated the sum of the values at both pointers.

If the sum was equal to the target, I returned true.

If the sum was smaller than the target, I moved the left pointer to the right to increase the sum.

If the sum was greater than the target, I moved the right pointer to the left to decrease the sum.

I repeated this process until the pointers crossed. If no matching pair was found, I returned false.

First, I understood that the water trapped at any position depends on the maximum height on its left and right sides.

I initialized two pointers: one at the start of the array (left) and one at the end (right).

I also maintained two variables to track the maximum height seen so far from the left and from the right.

I compared the heights at both pointers, as the smaller height determines how much water can be trapped at that position.

If the left height was smaller, I moved the left pointer forward and updated the left maximum.

If the current height was less than the left maximum, the difference contributed to the trapped water; otherwise, I updated the maximum height.

I followed the same logic on the right side when the right height was smaller.

Tip 1: Break the problem into smaller components, such as connection handling, message delivery, and data storage, before designing the solution.
Tip 2: Use real-time communication mechanisms like WebSockets or SignalR to ensure instant message exchange.
Tip 3: Consider scalability early by planning how messages will be handled when multiple users are online simultaneously.
Tip 4: Focus on reliability by addressing edge cases, such as connection drops and message ordering.

Tip 1:Clearly define the payment flow from initiation to confirmation and handle each step as an independent, well-validated process.
Tip 2: Design the system to be idempotent to avoid duplicate transactions in case of retries or network failures.
Tip 3: Handle failure scenarios gracefully by implementing retries, timeouts, and proper rollback or compensation mechanisms.