字符串-----按单词逆序

例如:将“I  am a girl” 逆序成“girl a am I”

两个步骤:第一,先按单词逆序得  “I ma a lrig”;  第二步,将整个句子逆序得 "girl a am I" 

#include <stdio.h>
#include <string.h>
#define MAXSIZE 1024

//交换首尾两个字符并向中间移动指针直到交叉
void ReverseWord(char *p, char *q)
{
	while (p < q)
	{
		char t = *p;
		*p = *q;
		*q = t;
		++p;
		--q;
	}	
}
char *Reverse(char *s)
{
	char *p = s;
	char *q = s;
//将前(n -1 )个单词逆序
	while (*q != '\0')
	{
		if (*q == ' ')
		{
			ReverseWord(p, q - 1);
			++q;
			p = q;
		}
		else
			++q;
	}
//将最后一个单词逆序
	ReverseWord(p, q - 1);
//将整个字符串逆序
	ReverseWord(s, q - 1);
	return s;
}

int main()
{
	char str[MAXSIZE];
	gets(str);
	int len = strlen(str);
	printf("%s\n", Reverse(str));
	return 0;
}

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转载自blog.csdn.net/weixin_39916039/article/details/81513793