SystemVerilog Testbench Introduction

SystemVerilog Testbench Architecture

APB Interface

APB Transaction

APB Generator

APB Driver

APB Driver Phase 2

APB Monitor

APB Scoreboard

APB Environment

APB Testbench Top

RISC-V Processor (YARP) Interface

YARP Transaction

YARP Generator

YARP Driver

YARP Data Memory Model

YARP Monitor

YARP Scoreboard

YARP Testbench Top

DVCon 26 Hackathon Problem

Array Sum Limit

Array Index Sum Limit

Ball Draw No Repeat

Conditional Even Probability

Even Odd Index Value

Five Consecutive Ones

Frequency Constraint

Grouped Ones

Index Value Range

Leap Year

Matrix Rotation

Non Adjacent Ones

Power of 4

Dynamic Ranges

Recent Four Unique

Row Max Unique

Subarray Max Sum

Three Duplicates Only

Tic Tac Toe

Unique 3D Array

Weighted Popcount

Unique Sum

Split Array into Queues

# Conditional Even Probability

## Problem Statement

Generate a sequence of single-byte values (8-bit unsigned integers) where the probability of generating an even or odd number depends on the previous number:

- If the previous value was **odd**: Next value is even with 75% probability, odd with 25% probability
- If the previous value was **even**: Next value is even with 25% probability, odd with 75% probability

This demonstrates conditional weighted randomization based on prior state.

## Constraints
- Value range: 0-255 (8-bit)
- Conditional probability distribution based on parity of previous value
- Pattern: Odd values tend to be followed by even values (75% chance), and even values tend to be followed by odd values (75% chance)
- Creates a "bouncing" pattern between even and odd numbers

## Examples

### Example 1:
```
Input: Start with value 5 (odd)
Output: Next value should be even with 75% probability
Possible valid sequences (75% of the time):
- [5, 10, ...] where 10 is even
- [5, 20, ...] where 20 is even
- [5, 100, ...] where 100 is even

Possible valid sequences (25% of the time):
- [5, 11, ...] where 11 is odd
- [5, 21, ...] where 21 is odd
```

### Example 2:
```
Input: Start with value 8 (even)
Output: Next value should be odd with 75% probability
Likely continuation:
- [8, 3, ...] where 3 is odd (75% chance)
- [8, 99, ...] where 99 is odd (75% chance)

Unlikely continuation (25% chance):
- [8, 10, ...] where 10 is even (25% chance)
```

### Example 3:
```
Input: Generate sequence starting from value 1 (odd)
Sequence: [1, 100, 55, 200, 127, ...]
Analysis:
- After 1 (odd): 100 (even) - follows 75% probability rule ✓
- After 100 (even): 55 (odd) - follows 75% probability rule ✓
- After 55 (odd): 200 (even) - follows 75% probability rule ✓
- After 200 (even): 127 (odd) - follows 75% probability rule ✓
Expected pattern: alternating even-odd with weights as specified
```

### Example 4:
```
Input: Validate [2, 5, 8, 3, 6, 1, 4, ...]
Trace:
- Start: 2 (even) → next should be odd (75%) or even (25%): next is 5 (odd) ✓
- prev=5 (odd) → next should be even (75%) or odd (25%): next is 8 (even) ✓
- prev=8 (even) → next should be odd (75%) or even (25%): next is 3 (odd) ✓
- prev=3 (odd) → next should be even (75%) or odd (25%): next is 6 (even) ✓
Output: Valid sequence following the conditional probability rules
```
