POJ 2456

 1 #include <iostream>
 2 #include <vector>
 3 #include <algorithm>
 4 using namespace std;
 5 
 6 unsigned int N;
 7 unsigned int C;
 8 vector<int> x;
 9 int stall;
10 
11 int main()
12 {
13     /***************************************************/ 
14     //input and preprocessing
15     
16     cin >> N >> C;
17     for(int i = 0; i < N; ++i)
18     {
19         int temp;
20         cin >> temp;
21         x.push_back(temp);
22     }
23     sort(x.begin(), x.end());
24     
25     
26     /***************************************************/ 
27     //solver
28     int lower = 0;
29     int upper = 1000000000;
30     int mid;
31     while(upper - lower > 1)
32     {
33         mid = (upper + lower) / 2;
34     
35         /***************************************************/ 
36         //calc
37         stall = 1;
38         for(int i = 0, j = 0; i < x.size(); )
39         {
40             if(x[i] - x[j] >= mid)
41             { 
42                 ++stall;
43                 j = i;
44                 ++i; 
45             }
46             else
47             {
48                 ++i;
49             }
50                 
51         }
52         //end calc
53         /***************************************************/ 
54         if(stall >= C)
55             lower = mid;
56         else
57             upper = mid;    
58     }
59     
60     /***************************************************/ 
61     //output
62     
63     cout << lower << endl;
64     return 0;
65 }