leetcode 最长公共前缀

def cm(s):
    
    s1=list(zip(*s))
    cc=''
    for k in s1:
        ss=list(set(k))
        if len(ss)==1:
            cc+=ss[0]
    return cc

a= ['flower', 'flow', 'flight']

print(cm(a))

def cm1(a):
    a.sort(key=len) 
    char=''
    for i in range(len(a[0])):
        temp=[]
        for j in range(len(a)):
            if a[0][i]==a[j][i]:
               temp.append(a[0][i])
        if len(temp)==len(a) :
            char+=a[0][i]
    return char
a= ['flower', 'flow', 'flight']
print(cm1(a))