[Solved] Suppose the problem is extended so that characters can be reused unlimited times (infinite supply), and you want to generate... Which approach fundamentally changes compared to the original problem? | Greedy Algorithms

Greedy Algorithms - Reorganize String (No Two Adjacent Same)

Suppose the problem is extended so that characters can be reused unlimited times (infinite supply), and you want to generate the lexicographically smallest string of length n with no two adjacent characters the same. Which approach fundamentally changes compared to the original problem?

AUse dynamic programming to count valid strings

BUse max heap with frequency counts as before

CUse backtracking to generate all permutations and pick lex smallest

DUse a greedy approach selecting the smallest available character different from previous

Step-by-Step Solution

Solution:

Step 1: Understand infinite supply variant
With infinite supply, frequency counts are irrelevant; problem reduces to counting or generating strings avoiding adjacency.
Step 2: Identify suitable approach
Dynamic programming is needed to count or generate lex smallest strings under adjacency constraints.
Step 3: Contrast with original greedy
Original greedy relies on finite frequencies; infinite supply breaks that assumption, requiring DP.
Final Answer:
Option A -> Option A
Quick Check:
Infinite supply requires DP, not greedy heap [OK]

Quick Trick: Infinite supply breaks frequency-based greedy, needs DP [OK]

Common Mistakes:

MISTAKES

Trying to reuse greedy heap
Ignoring infinite supply impact
Assuming backtracking is only way

Trap Explanation:

PITFALL

Candidates often try to apply original greedy heap approach incorrectly to infinite supply variant.

Interviewer Note:

CONTEXT

Tests ability to adapt approach to problem variants changing core assumptions.

Master "Reorganize String (No Two Adjacent Same)" in Greedy Algorithms

3 interactive learning modes - each teaches the same concept differently

Try It Solution Trace

More Greedy Algorithms Quizzes

Which approach fundamentally changes compared to the original problem?

Step 1: Understand infinite supply variant

Step 2: Identify suitable approach

Step 3: Contrast with original greedy

Final Answer:

Quick Check:

Want More Practice?