C语言——输入一个4位正整数，输出其逆数。

#define _CRT_SECURE_NO_WARNINGS 1#include<stdio.h>
int main()
{int i,j = 0;int a1,a2,a3,a4;printf("输入一个4位正整数：\n");scanf("%d",&i);a1 = i/1000;		a2 = i/100%10;	a3 = i/10%10;		a4 = i%10;		printf("千位a1=%d,百位a2=%d,十位a3=%d,个位a4=%d\n",a1,a2,a3,a4);j = 1000*a4 + 100*a3 + 10*a2 + a1;printf("逆数j=%d\n",j);return 0;
}