chapter2.py

import marimo

__generated_with = "0.14.17"
app = marimo.App(width="medium")


@app.cell
def _():
    return


@app.cell
def _():
    def gc_content_percentage(dna_sequence: str) -> float:
        """Calculate the GC content percentage of a DNA sequence."""
        # Convert sequence to uppercase for uniformity
        dna = dna_sequence.upper()
        # Count G and C nucleotides
        g_count = dna.count('G')
        c_count = dna.count('C')
        total_bases = len(dna)
    
        if total_bases == 0:
            return 0.0
    
        gc_percent = (g_count + c_count) / total_bases * 100
        return gc_percent

    # Prompt user for DNA sequence input
    if __name__ == "__main__":
        user_input = input("Enter a DNA sequence: ").strip()
        percentage = gc_content_percentage(user_input)
        print(f"GC content: {percentage:.2f}%")

    return


if __name__ == "__main__":
    app.run()