import time

def plusravno(copies):
	start = time.time()
	l = ['abc', 'def', 'ghi', 'jkl', 'mno', 'pqr', 'stu', 'vwx', 'yz0'] * copies
	s = ""
	for e in l:
		s += e
	end = time.time()
	print("%d strings concatenated in %.3f seconds" % (len(l), end - start))
	
def tochkajoin(copies):
	start = time.time()
	l = ['abc', 'def', 'ghi', 'jkl', 'mno', 'pqr', 'stu', 'vwx', 'yz0'] * copies
	s = ''.join(l)
	end = time.time()
	print("%d strings joined in %.3f seconds" % (len(l), end - start))
	
plusravno(1000000)
tochkajoin(1000000)