I am a student. student.a am I

#include <iostream>

//////////////////////////////////////////////////////////////////////////
///字符串反轉,不用庫函數, 單詞字母順序不變,只調整單詞順序爲反序: 如 I am a student.   student.a am I
///1. 斷詞
///2. 單詞反轉
///3. 整句反轉
/////////////////////////////////////////////////////////////////////////
void reversed_word(char *start, char *end)
{
	while(start < end)
	{
		char temp = *start;
		*start++ = *end;
		*end-- = temp;
	}
}

char * reversed_str (char *str)
{
	char *start = str;
	char *end = str;
	while(1)
	{
		if (*end == ' '|| *end == '\0')
		{
			if( *end == '\0')
				break;
			reversed_word(start, end - 1);
			while(*end == ' ')
			{
				end++;
			}
			start = end;
		}
		else
		{
			end++;
		}
	}
	printf("單個單詞反轉後輸出: %s\n", str);
	reversed_word(str, end-1);
	return str;
}

int main()
{
	char str[] = " i am  !./   a student.   ";
	printf("%s\n", str);
	printf("%s\n", reversed_str(str));
	return 0;
}