make_random_txt.sh

#!/bin/bash

# Check if the correct number of arguments is provided
if [ "$#" -ne 2 ]; then
    echo "Usage: $0 <filename> <number_of_characters>"
    exit 1
fi

# Get the filename and number of characters from the arguments
filename=$1
num_chars=$2

# Generate the random letters and save to the file
base_letters=("A" "T" "C" "G")
count=0

> "$filename" # Clear the file if it already exists

for ((i=0; i<num_chars; i++)); do
    random_letter=${base_letters[$RANDOM % 4]}
    echo -n "$random_letter" >> "$filename"
    count=$((count + 1))
    if [ $count -eq 50 ]; then
        echo "" >> "$filename"
        count=0
    fi
done

# If the last line is not empty, add a newline at the end of the file
if [ $count -ne 0 ]; then
    echo "" >> "$filename"
fi

echo "Generated $num_chars random letters and saved to $filename"