反转一句话的单词顺序

即实现一个功能，可以将一句话中的单词顺序反过来，比如：

America and China are both great countries.

反过来显示就应该是：

countries. great both are China and America

单词的分隔符以空格符为准。

思路很简单，分两步：

1、将整句话看作一个单词，进行逆序：

.seirtnuoc taerg htob era anihC dna aciremA

2、以空格为分隔符，将每个单词再进行逆序：

countries. great both are China and aciremA

下面是我自己写的一个简单的实现，不过总感觉有点别扭，可能哪里还有问题吧。

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

void reverse_word(char *word, int len)
{
    char tmp;
    char *end = word + len - 1;
    while (word < end) {
        tmp = *word;
        *word = *end;
        *end = tmp;
        word++;
        end--;
    }
}

void reverse_sentence(char *p, char *delim)
{
    int len = strlen(p);
    reverse_word(p, len);

    int count = 0;
    while ('\0' != *p) {
        if (isspace(*p)) {
            reverse_word(p - count, count);
            count = 0;	// 单词长度
            while (isspace(*++p));
            continue;
        }
        p++;
        count++;
    }
}

int main(int argc, char **argv)
{
    char sentence[] = "  I   from   nwpu, my name is cq!      ";
    printf("before reverse: ^%s$\n", sentence);
    reverse_sentence(sentence, " ");
    printf(" after reverse: ^%s$\n", sentence);
}