# FILE: count-fasta.py
# AUTHOR: William Stafford Noble
# CREATE DATE: 18 January 2007
# PROJECT: GENOME 559
import sys

# Make sure we got a filename on the command line.
if (len(sys.argv) != 2):
    print("USAGE: count-fasta.py <file>")
    sys.exit(1)

# Open the file for reading.
fasta_file = open(sys.argv[1], "r")

num_seqs = 0
for line in fasta_file:
    # Increment if this is a new sequence.
    if (line[0] == ">"):
        num_seqs += 1
print(num_seqs)
fasta_file.close()