Python Utils.chop Exemples

Exemple #1

def p46():
	#getting precalculated primes and squares:
	u = Utils()
	primes = u.sieve(6000)
	squares = [i * i for i in range(1, 101)]
	#start searching at 15:
	o = 15
	while o < 5800:
		#is the test number prime?
		if u.chop(o, primes) != -1:
			#yeap, go to next one:
			o += 2
			continue
		#nope, begin testing:
		ind = 0
		found = False
		while o - primes[ind] > 0:
			s = (o - primes[ind]) / 2
			#found desired decomposition?
			if u.chop(s, squares) != -1:
				#yep, break out:
				found = True
				break
			#nope, try next prime:
			else:
				ind += 1
			#found possible candidate:
		if not found:
			print o
		#keep searching:
		o += 2

Exemple #2

def p44():
    u = Utils()
    limit = 3000
    pl = [u.pentagonal(i) for i in xrange(limit)]
    for a in xrange(1, limit):
        for b in xrange(1, limit):
            if a > b:
                c = pl[a] + pl[b]
                d = pl[a] - pl[b]
                if u.chop(c, pl) > -1 and u.chop(d, pl) > -1:
                    print a, b, pl[a], pl[b],\
                        pl[pl.index(c)],\
                        pl.index(c),\
                        pl[pl.index(d)],\
                        pl.index(d)