华为上机（2）输出一个字符串中最长的一个单词

/输出一个字符串中最长的一个单词 如：input[] = "no pains,no gain",output[] = "pains";

函数原型：void func(char *input,char *output);

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

void f(char *input,char *output)
{
	char *p = input;
	char *q = p + 1 ;

    int max_len = 0;
	while(*p)
	{
		while(!isspace(*q) && !ispunct(*q))
			++q;

		int len = (int)(q-p);
		
		if(len > max_len)
		{
			max_len = len;
			strncpy(output,p,len);
		}

		p = q+1;
		q = q+2;
	}
}

int main()
{
	char input[] = "No pains,no gain!";
//	char input1[] = "what is your favouriate food,and how old are you?";
    char output[30] = "";

    f(input,output);

	puts(output);

	return 0;
}