c语言: 从键盘上输入正数顺序,从屏幕上以颠倒次序输出.如输入1234,输出4321

#include<stdio.h>
main(){
int a,b,c,d;
scanf("%1d%1d%1d%1d",&a,&b,&c,&d);
printf("%d%d%d%d",d,c,b,a);
}

void change_str2(char * resource_str)
{
char object_str[128];
/* 定义单词开始指针,单词结尾指针,*/
char * begin_of_word, * end_of_word, * work_of_obj;
int word_no=-1;

begin_of_word=end_of_word=next_word=resource_str;
work_of_obj=object_str;
/* 当句子没有结束时循环 */
while( * next_word != '.' )
{
end_of_word++;
/* 当扫描到空格或者句号时是一个单词的结尾 */
if( * end_of_word == ' ' || * end_of_word == '.')
{
if ( * next_word != '.' );
* work_of_obj++ = ' ';
word_no++;
if( * end_of_word == '.')
next_word = end_of_word;
else
{
next_word = end_of_word+1;
}
end_of_word--;
/*将单词反序*/
while( end_of_word >= begin_of_word)
{