问题：求字符串中重复出现且长度最长子字符串，要求输出：符合条件子字符串、其重复出现次数、其首字母位置。

分析：后缀数组方法求解。

python版代码：

# 问题：求字符串中重复出现且长度最长子字符串，要求输出：符合条件子字符串、其重复出现次数、其首字母位置。
# 分析：后缀数组方法求解。
# by chasdmeng

def build_suffix_array(suffix_array, text_string):
    for i in range(len(text_string)):
        suffix_array.append(text_string[i:])
    suffix_array.sort()

def comlen(str_a, str_b):
    max_len = 0
    for i in range(1, len(str_a)+1):
        max_len = i if str_a[:i]==str_b[:i] else max_len

    return max_len

def longset_repeat_substring(suffix_array, text_string):
    max_len, max_idx = 0, 0
    t={}
    for i in range(len(text_string) - 1):
        com_len= comlen(suffix_array[i], suffix_array[i+1])
        if com_len in t:
            t[com_len]+=1
        else:
            t[com_len] = 2
        [max_len, max_idx] = [com_len, i] if com_len > max_len else [max_len, max_idx]
        loc = [len(text_string)-len(suffix_array[max_idx + i]) + 1 for i in range(t[max_len])]
        loc.sort()
    return suffix_array[max_idx][:max_len], t[max_len], loc

if __name__ == ‘__main__‘:
    suffix_array = []
    text_string = "yyabcdabjcabceg"

    build_suffix_array(suffix_array, text_string)
    substring, time, location = longset_repeat_substring(suffix_array, text_string)
    print ‘\nIn \‘‘, text_string, ‘\‘, the longest string‘, ‘\‘‘, substring, ‘\‘occuers‘,            time, ‘times‘,‘,the first character position‘, ‘,‘.join([str(i) for i in location]), ‘.‘