x, y, z = input().split()
x = int(x)
y = int(y)
if z == "0":
    print(0)
    exit(0)
le = len(z)
dec = 0
d = 1
for i in range(le - 1, -1, -1):
    t = 0
    if z[i] <= '9' and z[i] >= '0':
        t = ord(z[i]) - ord('0')
    if z[i] <= 'Z' and z[i] >= 'A':
        t = ord(z[i]) - ord('A') + 10
    if z[i] <= 'z' and z[i] >= 'a':
        t = ord(z[i]) - ord('a') + 36
    dec = t * d + dec
    d = x * d
ans = []
while dec > 0:
    t = dec % y
    dec = dec // y
    if t < 10:
        ans.append(chr(t + ord('0')))
    if t >= 10 and t < 36:
        ans.append(chr(t - 10 + ord('A')))
    if t >= 36:
        ans.append(chr(t - 36 + ord('a')))
ans.reverse()
for i in ans:
    print(i, end = "")