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

void change(char *str)
{
    char temp = 0;
    char *p = str;
    char *start = str;
    char *end = str;

    while(*p !='\0')
    {
        p++;
        end++;
    }
    end = p - 1;
    p = str;
    while(*p !='\0')
    {
        while(start < end)
        {
            temp = *start
 
;
            *start = *end;
            *end = temp;
            start++;
            end--;
        }
        p++;
    }

}

void change1(char *str)
{
    char *p = str;
    char *start = p;
    char *end = p;
    char temp;

    while(*p != '\0')
    {
        if(*p == ' '||*p == '\0')
        {
            end = p-1
 
;
            while(start < end)
            {
                temp = *start;
                *start = *end;
                *end = temp;
                start++;
                end--;
            }
            start = end = p+1;
        }
        p++;
    }
    end = p-1;
    while(start < end)
    {
        temp = *start
 
;
        *start = *end;
        *end = temp;
        start++;
        end--;
    }
}

int main()
{
    char str[100] = {0};

    printf("input:\n");
    gets(str);

    change(str);
    change1(str);

    printf("the result is:%s\n",str);

}