x, y, z = input().split()
x = int(x)
y = int(y)
n = 0
for c in z:
	d = ord(c) - ord('0') if '0' <= c <= '9' else  ord(c) - ord('A') + 10 if 'A' <= c <= 'Z' else ord(c) - ord('a') + 36
	n = x * n + d
s = ""
if n == 0:
	print(0)
	exit(0)
while n != 0:
	d = n % y
	if d < 10:
		s += str(d)
	elif d < 36:
		s += chr(ord('A') + d - 10)
	else:
		s += chr(ord('a') + d - 36)
	n //= y
for i in range(len(s) - 1, -1, -1):
	print(s[i], end='')
print()