[C++知识库]C语言练习--倒置字符串

题目：将一句话的单词倒置，标点不倒置。比如：I like beijing. 经过函数后变为：beijing. like I

输入描述：输入用例长度不超过100

输出描述：依次输出倒置之后的字符串，以空格分割

解题思路：

I like beijing.

I ekil .gnijieb? ? ? 将每个单词一一逆序

beijing. like I? ? ? 将整个字符串逆序

举个简单的例子：abc def hi.

#include<stdio.h>
#include<assert.h>
#include<string.h>
void reverse(char* left, char* right)
{
	assert(left&&right);  //断言 避免传进来的left和right是空指针
	while (left<right)
	{
		char tmp = *left;
		*left = *right;
		*right = tmp;
		left++;
		right--;
	}
}

int main()
{
	char arr[100] = { 0 };
	gets(arr);
	char* start = arr;
	char* end = start;
	int len = strlen(arr);
	while (*end != '\0')
	{
		while (*end != ' '&& *end != '\0')   
		{
			end++;
		}
		reverse(start, end - 1);
		if (*end == '\0')
			start = end;
		else
			start = end + 1;
		end = start;
	}
	reverse(arr, arr + len - 1);
	printf("%s\n", arr);
	return 0;
}

运行结果：