PAT 1064 朋友数

#include<stdio.h>
#include<iostream>
#include <algorithm>
using namespace std;
int main()
{
    int n;
    int i;
    int count=0;
    int sum=0;
    scanf("%d",&n);
    int number[n];
    int s[n];
    int s2[n];
    for(i=0;i<n;i++){
        scanf("%d",&number[i]);
        if(number[i]>999) count=4;
        else if(number[i]>99) count=3;
        else if(number[i]>9) count=2;
        else count=1;
        while(count--){
            sum+=number[i]%10;
            number[i]=number[i]/10;
        }
        s[i]=sum;
        sum=0;
    }
    sort(s,s+n);
    sum=0;
    count=0;
    for(i=0;i<n;i++){
            if(s[i]!=sum){
                s2[count]=s[i];
                count++;
                sum=s[i];
            }       
        }   
    sum=0;
    printf("%d\n",count);
    for(i=0;i<count;i++){
       if(i<count-1) printf("%d ",s2[i]);
       else printf("%d\n",s2[i]); 
    }
    return 0;
 }