def cal(n):
    if n >='0' and n <='9':
        return ord(n) - ord('0')
    if n >='a' and n <= 'z':
        return ord(n) - ord('a') + 36
    return ord(n) - ord('A') + 10

def cal2(n):
    if(n<=9):
        return n + ord('0')
    if(n<=35):
        return n + ord('A') - 10
    else:
        return n + ord('a') - 36

s = input()
temp = s.split(' ')
n = int(temp[0])
m = int(temp[1])
value = temp[2]
Ans = 0
for i in range(len(value)):
    Ans = Ans * n + int(cal(value[i]))
a = []

if Ans == 0:
    print(0)

while Ans != 0:
    a.append(cal2(Ans % m))
    Ans = Ans // m
for i in range(len(a)-1,-1,-1):
    print(chr(a[i]),end = "")