题解 | #查找两个字符串a,b中的最长公共子串#

from operator import itemgetter
str_i = input()
str_j = input()
if (len(str_i) > len(str_j)):
    str_i, str_j = str_j, str_i
for i in range(len(str_i) - 1):
    str_j = "\r" + str_j + "\r"
max_len = 0
max_len_pos = -1
lst = []
for j in range(len(str_j) - len(str_i) + 1):
    maxlen = 0
    te_len = 0
    pos = 0
    for i in range(len(str_i)):
        if str_j[j:j + len(str_i)][i] == str_i[i]:
            te_len = te_len + 1
            if te_len >= maxlen:
                maxlen = te_len
                pos = i-maxlen+1
        else:
            te_len = 0
    #print(maxlen,pos)
    lst.append((maxlen,pos))
#print(sorted(lst,key=itemgetter(0)))
a = sorted(lst,key=itemgetter(0))[-1][0]
zuobiao = sorted(list(filter(lambda x :x[0]==a,lst)),key=itemgetter(1))[0]
#print(zuobiao)
print(str_i[zuobiao[1]:zuobiao[1]+zuobiao[0]])

滑动窗口