백준 6378 디지털 루트

www.acmicpc.net/problem/6378

6378번: 디지털 루트

result=[]
while(1):
    n=int(input())
    m=n
    d=0
    if n==0:
        break
    while(1):
        if m==0:
            if d<10:
                break
            else:
                m=d
                d=0
        d+=m%10
        m=m//10
        
    result.append(d)
for i in result:
    print(i)

while(1):
    n=input()
    
    if n=='0':
        break
    while(1):
        if len(n)<=1:
            break
        m=0
        for i in range(len(n)):
            m+=int(n[i])
        n=str(m)
    print(n)