UVA-11728 Alternate Task

 1 # include<iostream>
 2 # include<cstdio>
 3 # include<set>
 4 # include<cstring>
 5 # include<algorithm>
 6 using namespace std;
 7 int ans[1005];
 8 set<int>s;
 9 void init()
10 {
11     set<int>::iterator it;
12     memset(ans,-1,sizeof(ans));
13     for(int i=1;i<=10000;++i){
14         s.clear();
15         for(int j=1;j*j<=i;++j){
16             if(i%j==0){
17                 s.insert(j);
18                 s.insert(i/j);
19             }
20         }
21         int sum=0;
22         for(it=s.begin();it!=s.end();++it)
23             sum+=(*it);
24         if(sum<=1000)
25             ans[sum]=i;
26     }
27 }
28 int main()
29 {
30     init();
31     int n,cas=0;
32     while(scanf("%d",&n)&&n)
33         printf("Case %d: %d\n",++cas,ans[n]);
34     return 0;
35 }