Missionaries And Cannibals Puzzle

Solve the missionaries-and-cannibals river crossing with an ASCII diagram, contrasting gpt-4o built-in chain-of-thought with a deepseek-reasoner reasoning model.

Demonstrates built-in and DeepSeek-backed reasoning for logic puzzle solving.

logical_puzzle.py

"""
Missionaries And Cannibals Puzzle
=================================

Demonstrates built-in and DeepSeek-backed reasoning for logic puzzle solving.
"""

from agno.agent import Agent
from agno.models.deepseek import DeepSeek
from agno.models.openai import OpenAIChat

# ---------------------------------------------------------------------------
# Create Agents
# ---------------------------------------------------------------------------
task = (
    "Three missionaries and three cannibals need to cross a river. "
    "They have a boat that can carry up to two people at a time. "
    "If, at any time, the cannibals outnumber the missionaries on either side of the river, the cannibals will eat the missionaries. "
    "How can all six people get across the river safely? Provide a step-by-step solution and show the solutions as an ascii diagram"
)

cot_agent = Agent(
    model=OpenAIChat(id="gpt-4o"),
    reasoning=True,
    markdown=True,
)

deepseek_agent = Agent(
    model=OpenAIChat(id="gpt-4o"),
    reasoning_model=DeepSeek(id="deepseek-reasoner"),
    markdown=True,
)

# ---------------------------------------------------------------------------
# Run Agents
# ---------------------------------------------------------------------------
if __name__ == "__main__":
    print("=== Built-in Chain Of Thought ===")
    cot_agent.print_response(task, stream=True, show_full_reasoning=True)

    print("\n=== DeepSeek Reasoning Model ===")
    deepseek_agent.print_response(task, stream=True, show_full_reasoning=True)

Run the Example

1. Set up your virtual environment

   Mac

   uv venv --python 3.12
   source .venv/bin/activate
   

   uv venv --python 3.12
   .venv\Scripts\activate
   
2. Install dependencies

   uv pip install -U agno openai
   
3. Export your API keys

   Mac/Linux

   export DEEPSEEK_API_KEY="your_deepseek_api_key_here"
   export OPENAI_API_KEY="your_openai_api_key_here"
   

   $Env:DEEPSEEK_API_KEY="your_deepseek_api_key_here"
   $Env:OPENAI_API_KEY="your_openai_api_key_here"
   
4. Run the example

   Save the code above as logical_puzzle.py, then run:

   python logical_puzzle.py
   

Full source: cookbook/10_reasoning/agents/logical_puzzle.py