Number Max: Find Maximum of Two Numbers Without Comparison Operators (CTCI 16.7)

TL;DR

• The Problem: CTCI problem 16.7 technical mechanics.
• The Approach: CTCI problem 16.7: find maximum of two integers without using if-else or comparison operators using bitwise sign shift.
• Complexity: Optimal Time and Memory bounds.

This article provides a clear breakdown of CTCI problem 16.7.

1. Context and Problem Statement

CTCI problem 16.7: find maximum of two integers without using if-else or comparison operators using bitwise sign shift.

2. Technical Code & Mechanics

public static int getMax(int a, int b) {
    int k = sign(a - b);
    int q = flip(k);
    return a * k + b * q;
}
private static int sign(int a) { return flip((a >> 31) & 0x1); }
private static int flip(int bit) { return 1 ^ bit; }

3. Key Takeaways and Edge Cases

Always test boundary conditions and invalid input states.