【数据结构和算法面试题】连续最长数字串

int continumax(char *outputstr, char * inputstr){
	if (NULL == inputstr) return 0;

	char *p = inputstr;
	char *q = inputstr;// 记录最长字串的开始
	int length = 0;
	int max_len = 0;// 记录最大的长度
	while(*p != '\0'){
		if (!isdigit(*p)){
			length = 0;
			p ++;
			continue;
		}

		length ++;
		if (length > max_len){
			max_len = length;
			q = p - length + 1;
		}
		p ++;
	}
	int i = 0;
	for (i = 0; i < max_len; i++){
		outputstr[i] = *q;
		q ++;
	}
	outputstr[i] = '\0';
	return max_len;
}