Discription
Eighth-grader Vova is on duty today in the class. After classes, he went into the office to wash the board, and found on it the number n. He asked what is this number and the teacher of mathematics Inna Petrovna answered Vova that n is the answer to the arithmetic task for first-graders. In the textbook, a certain positive integer x was given. The task was to add x to the sum of the digits of the number x written in decimal numeral system.
Since the number n on the board was small, Vova quickly guessed which x could be in the textbook. Now he wants to get a program which will search for arbitrary values of the number n for all suitable values of x or determine that such x does not exist. Write such a program for Vova.
Input
The first line contains integer n (1?≤?n?≤?109).
Output
In the first line print one integer k — number of different values of x satisfying the condition.
In next k lines print these values in ascending order.
Example
Input
21
Output
115
Input
20
Output
0
Note
In the first test case x?=?15 there is only one variant: 15?+?1?+?5?=?21.
In the second test case there are no such x.
很显然每位数的和的贡献不可能太大，对于题目的范围来说肯定是<100的，所以枚举比n小100之内的数就行了。。
#include<bits/stdc++.h>
#define ll long long
using namespace std;
int num[1005];
int n,m,k;
inline int get(int x){
int an=0,nxt;
while(x){
nxt=x/10;
an+=x-nxt*10;
x=nxt;
}
return an;
}
int main(){
cin>>n;
k=max(1,n-100);
for(int i=k;i<n;i++) if(i==n-get(i)) num[++m]=i;
printf("%d\n",m);
for(int i=1;i<=m;i++) printf("%d\n",num[i]);
return 0;
}
原文地址：https://www.cnblogs.com/JYYHH/p/8450356.html