Titan.email OA Experience 2026 | 3 Coding Questions | Exact Codeforces Matches

Titan.email OA Experience 2026 | 3 Coding Questions | Exact Codeforces Matches

I recently appeared for the Titan.email Online Assessment. The OA had 3 coding questions, and after checking them later, all three turned out to be exact matches with Codeforces problems.

The overall difficulty was quite high and the test was clearly more competitive-programming oriented than standard easy/medium LeetCode OAs.

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Q1. Weird Computation

We were given an array a and had to compute:

[\sum_{l=1}^{n}\sum_{r=l}^{n} f(l,r)\cdot(r-l+1)]

where

[f(l,r)=a_l\oplus a_{l+1}\dots\oplus a_r]

In simple terms, for every subarray:

• Find its XOR.
• Multiply that XOR by the length of the subarray.
• Add the contribution of all subarrays.

Exact Match

Codeforces 1879D - Sum of XOR Functions

Topics

• Bit Manipulation
• Prefix XOR
• Contribution Technique
• Prefix Sums
• Bitwise Optimization

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Q2. Chain Lightning

We were given an array representing the strengths of monsters.

We could choose the starting monster from any position, and we had to find the minimum initial power required to defeat all monsters while satisfying the required power condition at every attack.

One test case I remember was:

[5, 3, 1, 6, 2, 4]

Output:

9

Exact Match

Codeforces 1901D - Yet Another Monster Fight

The original Codeforces problem also uses the idea of chain lightning, so Titan had essentially used the same problem/theme.

Topics

• Greedy
• Prefix Maximum
• Suffix Maximum
• Arrays
• Optimal Starting Position

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Q3. Maximum Median of Workers

There were multiple test cases.

For each test case, we were given:

• n workers
• A total budget
• For every worker, a range [a, b]

We had to assign an appropriate value/salary to each worker such that:

a[i] <= salary[i] <= b[i]

while staying within the given total budget.

The objective was to maximize the median salary of all workers.

Exact Match

Codeforces 1251D - Salary Changing

Topics

• Binary Search on Answer
• Greedy
• Sorting
• Median
• Feasibility Check

The main idea is to binary search on the possible median and check whether it is possible to assign salaries while keeping the total cost within the budget.

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Final Question List

Titan.email OA Question	Exact Match
Weird Computation	CF 1879D - Sum of XOR Functions
Chain Lightning	CF 1901D - Yet Another Monster Fight
Maximum Median / Workers Budget	CF 1251D - Salary Changing

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Overall Experience

This was definitely one of the tougher OAs I have given.

All three questions required a non-trivial observation before implementation, and solving them efficiently required familiarity with competitive-programming techniques rather than only standard DSA patterns.

The question set covered:

• Bit Manipulation
• Prefix XOR
• Contribution Technique
• Greedy
• Prefix/Suffix Precomputation
• Binary Search on Answer
• Sorting
• Median Optimization

If you are preparing for Titan.email, I would strongly recommend practicing Codeforces 1600-1900 rated problems, especially problems involving binary search on answer, greedy observations, prefix/suffix techniques and bit manipulation.

If anyone else appeared for the same Titan.email OA, feel free to share your experience or approach in the comments.