Minimum Number of Steps to Make Two Strings Anagram II
A medium-tier problem at 73% community acceptance, tagged with Hash Table, String, Counting. Reported in interviews at Wealthfront and 0 others.
Wealthfront has asked this one, and it's a straightforward frequency-counting problem with a 72% acceptance rate. You're given two strings and need to find the minimum number of character changes to make them anagrams of each other. The trick is that both strings can be modified, not just one. Most candidates initially solve it wrong by counting mismatches in only one direction. StealthCoder will surface the correct frequency-table approach in seconds if you blank during the live OA.
Companies that ask "Minimum Number of Steps to Make Two Strings Anagram II"
Minimum Number of Steps to Make Two Strings Anagram II is the kind of problem that decides whether you pass. StealthCoder reads the problem on screen and surfaces a working solution in under 2 seconds. Invisible to screen share. The proctor sees nothing. Made by an Amazon engineer who watched the leaked-problem repo become an industry secret. He decided you should have it too.
Get StealthCoderThe core pattern is character frequency counting. Build a frequency map for both strings, then for each character, the cost is the absolute difference in their counts. Sum all differences and divide by two (since each change fixes two characters at once). The gotcha is recognizing that changes are bidirectional. You're not transforming string A into string B. You're meeting in the middle. Common failure mode: forgetting the division by two, or only counting characters present in one string. Hash Table and Counting are your topics here. When you hit this live and the obvious approach feels off, StealthCoder runs invisibly and hands you the working solution so you move on.
Pattern tags
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Make sure you actually pass it.
Minimum Number of Steps to Make Two Strings Anagram II recycles across companies for a reason. It's medium-tier, and most candidates blank under the timer. StealthCoder is the hedge: an AI overlay invisible during screen share. It reads the problem and surfaces a working solution in under 2 seconds. Made by an Amazon engineer who watched the leaked-problem repo become an industry secret. He decided you should have it too. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Minimum Number of Steps to Make Two Strings Anagram II interview FAQ
What's the actual trick to this problem?+
You're not forcing one string into another. You're finding the total character frequency delta and dividing by two, since each operation fixes two positions. Build frequency maps for both strings, sum absolute differences per character, divide by two. That's the whole algorithm.
Is this still asked at Wealthfront and similar shops?+
Wealthfront has confirmed this one. It's a medium-difficulty string problem, so yes, it circulates. The 72% acceptance rate suggests it's not a trip-up problem for prepared candidates, but plenty of people solve it wrong the first time.
How does this differ from the first Anagram problem?+
The key difference is bidirectional modification. In the first version, you'd only modify one string. Here, both can change, which cuts the total operations in half. That division-by-two step is where most mistakes happen.
Can I solve this without a hash table?+
Technically yes, you could use an array if the character set is bounded (26 letters), which is faster. But a hash table works fine and is more general. Either approach passes.
What's the time and space complexity I should know?+
Time is O(n plus m) where n and m are string lengths. Space is O(1) if using a fixed 26-letter alphabet, or O(k) where k is the unique character count. This is a linear, efficient problem once you get the logic right.
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