求一個字元串中連續出現的次數最多的子串[C語言實作]

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#define MAX_SIZE 50

int find_con_sub(char *str, char **ret);

int main()
{
        char str[] = "aabcdabcdabcdef";
        char *ret = NULL;
        int time = con_sub(str, &ret);
		if (time != 1)
		{
			printf("%s occurrs %d times in %s!\n", ret, time, str);
		}
		else
		{
			printf("%s don't have continus sub str!\n", str);
		}
		free(ret);
		ret = NULL;
        return 0;
}

int con_sub(char *str, char **ret)
{
        int max_time = 0;//連續出現的最多次數
        int ret_len = 0;//連續出現的字元串的長度
        char *addr = NULL;//連續出現字元串的起始位址
		int i,j,k;
		int temp_time = 0;
        int len = strlen(str);

        char *a[MAX_SIZE];//= (char **)malloc(sizeof(char *)*len);指針數組用于存儲字尾數組
	
        //生成字尾數組
        for(i=0; i<len; i++)
                a[i] = &str[i];

        //重複字元串的長度範圍為1到(len+1)/2
        for(i=1; i<=(len+1)/2; i++)
        {
                //當重複的字元串長度為i的時候，如果是連續出現的，那麼第j和第j+i個字尾數組前面為重複的字元串
                for(j=0; j+i<=len-1; j+=1)
                {
                        k = j;
                        temp_time = 1;

                        while(k+i <= len-1 && strncmp(a[k], a[k+i], i) == 0)
                        {
                                temp_time++;
                                k += i;
                        }

                        if(temp_time > max_time)
                        {
                                max_time = temp_time;
                                ret_len = i;
                                addr = a[k];
                        }
                }
        }

		*ret = (char*) malloc(sizeof(char) * (ret_len+1));
		strncpy(*ret, addr, ret_len);	
		
		(*ret)[ret_len] = '\0';

        return max_time;
}