OP_NOT - Boolean Inversion

5. OP_NOT — Boolean Inversion

Opcode Reference

Opcode:     OP_NOT
Hex:        0x91
Decimal:    145
Input:      a
Output:     !a  (1 if a == 0, else 0)

Overview

OP_NOT performs a boolean NOT operation. It does not perform bitwise negation — instead it treats the top stack element as a boolean and inverts it. If the top element is 0 (or the empty byte array), OP_NOT pushes 1. For any non-zero value, it pushes 0.

Truth Table

``` Input | Output