BNUOJ 34982 Beautiful Garden

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3 const int maxn = 50;
 4 int d[maxn],n;
 5 map<int,int>mp;
 6 int main() {
 7     int kase,m;
 8     scanf("%d",&kase);
 9     for(int cs = 1; cs <= kase; ++cs) {
10         scanf("%d",&n);
11         mp.clear();
12         for(int i = 0; i < n; ++i) {
13             scanf("%d",d+i);
14             mp[d[i]]++;
15         }
16         if(n <= 2) {
17             printf("Case #%d: %d\n",cs,0);
18             continue;
19         }
20         sort(d,d+n);
21         int ret = 50;
22         for(int i = 0; i < n; ++i) {
23             for(int j = i + 1; j < n; ++j) {
24                 int ds = d[j] - d[i],cnt = n-1;
25                 if(!ds) {
26                     ret = min(ret,n - mp[d[j]]);
27                     continue;
28                 }
29                 int now = d[i];
30                 for(int k = 1; k < n; ++k) {
31                     now += ds;
32                     if(mp[now]) cnt--;
33                 }
34                 int pre = d[i];
35                 ret = min(ret,cnt);
36                 for(int k = 1; k < n; ++k) {
37                     pre -= ds;
38                     cnt += (mp[now]?1:0) - (mp[pre]?1:0);
39                     now -= ds;
40                     ret = min(ret,cnt);
41                 }
42             }
43         }
44         printf("Case #%d: %d\n",cs,ret);
45     }
46     return 0;
47 }