反序数

#include <iostream>
#include <cstdio>
using namespace std;
int main(){
    int buf[5];//用buf保存从整数中拆解出来的数位数字
    for(int i = 1000; i <= (10000 / 9); i++){
        int tmp = i, num = 0, pos = 0;//tmp记录i的值,num记录反序数,pos记录当前下标
        while(tmp > 0){
            buf[pos] = tmp % 10;
            num = num * 10 + buf[pos++];
            tmp /= 10;
        }
        if(num == (i * 9)){
            printf("%d\n", i);//1089
        }
    }
    return 0;
}