input = open('data1.txt','r')
output = open('out1.txt', 'w')

minute = (30 * 5) * 60.0
for x in input.readlines():
	temp = x.split()
	#print str(int(round(minute/int(temp[0])))) + '\n'
	output.write(str(int(round(minute / int(temp[0])))) + '\n')
output.close()