python3 simple easy intuitive

def marsExploration(s): # Define the original SOS message original_sos = "SOS"

# Use list comprehension and enumerate to count altered letters
# Iterate over each index i and character char in the input string s
# Check if the character is different from the corresponding character in the original SOS message
# The use of i % 3 ensures cycling through the characters of the original SOS message
# Increment the altered_count for each altered letter
altered_count = sum(1 for i, char in enumerate(s) if char != original_sos[i % 3])

return altered_count