n=eval(input())
a=input()
m=eval(input())
l=['0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F']
def check(s):
    if s=='A':return 10
    if s=='B':return 11
    if s=='C':return 12
    if s=='D':return 13
    if s=='E':return 14
    if s=='F':return 15
def ten(s,key):
    cnt=0
    k=0
    for i in range(-1,-len(s)-1,-1):
        if s[i] in '0123456789':
            k+=int(s[i])*key**cnt
        else:
            k+=check(s[i])*key**cnt
        cnt+=1
    return k
n1=ten(a,n)
x=''
while n1!=0:
    x=str(l[n1%m])+x
    n1=n1//m
print(x)

为什么会RE啊