Mic Check Three

Platform: CUSTOM | Category: Reversing | Type: Challenge | Difficulty: Easy | OS: N/A | **Author: XESXOR Techniques: constraint_solving_manual, source_code_analysis

Summary

Walkthrough of the CUSTOM Reversing Mic Check Three. Language: C. Source code provided. Flag checker with multiple character position constraints.

Description

Language: C. Source code provided. Flag checker with multiple character position constraints.

Analysis

Constraints from source code:

• Length = 17
• atoi(input) == 333 → first characters "333"
• Positions 5, 7, 11 = 'o'
• Positions 9, 13, 15, 17 are equal to each other and = '0'
• Positions 4, 6, 8, 10, 12, 14, 16 are equal to each other and = 'g'

Solution

Building the string by positions (1-indexed):

Pos: 1  2  3  4  5  6  7  8  9  10 11 12 13 14 15 16 17
Chr: 3  3  3  g  o  g  o  g  0  g  o  g  0  g  0  g  0

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Key Takeaways / Lessons

• Mastering constraint_solving_manual, source_code_analysis was key to this challenge.
• Always check for common misconfigurations and verify assumptions.

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Crafted by XESXOR Research • 2026-03-09 • CUSTOM • Mic Check Three • Difficulty: Easy