USACO 3.2 Stringsobits 

 1 /*
 2 PROG: kimbits
 3 ID: jiafeim1
 4 LANG: C++
 5 */
 6 #include <algorithm>
 7 #include <iostream>
 8 #include <fstream>
 9 #include <string>
10 using namespace std;
11 
12 std::ofstream fout("kimbits.out");
13 
14 unsigned long upper[35][35]={0};
15 void work(unsigned long n, unsigned long l, unsigned long i)
16 {
17     unsigned long s;
18  
19     if(n == 0)
20         return;
21  
22     s = upper[n-1][l];
23     if(s < i) {
24         fout<<"1";
25         work(n-1, l-1, i-s);
26     } else {
27         fout<<"0";
28         work(n-1, l, i);
29     }
30 }
31 
32 
33 int main()
34 {
35     std::ifstream fin("kimbits.in");
36     
37     unsigned long n,l,i;
38     fin>>n>>l>>i;
39 
40     unsigned long count = 0;
41 
42     unsigned long cur = 1,temp;
43 
44     for(int i = 0;i!=n;++i)
45     {
46         upper[0][i] = 1;
47     }
48     
49     for(unsigned long len=1;len<=n;++len)
50     {
51         upper[len][0] = 1;
52         for(unsigned long gr = 1;gr<len;++gr)
53         {
54             upper[len][gr]=upper[len-1][gr]+upper[len-1][gr-1];
55         }
56         upper[len][len] = upper[len-1][len-1] << 1;
57         for(int i = len+1;i<=l;++i) upper[len][i] = upper[len][len];
58             
59     }
60 
61     work(n,l,i);
62 
63     fout<<endl;
64     fin.close();
65     fout.close();
66     return 0;
67 }
TASK: kimbits
LANG: C++

Compiling...
Compile: OK

Executing...
   Test 1: TEST OK [0.000 secs, 3032 KB]
   Test 2: TEST OK [0.000 secs, 3032 KB]
   Test 3: TEST OK [0.000 secs, 3032 KB]
   Test 4: TEST OK [0.000 secs, 3032 KB]
   Test 5: TEST OK [0.000 secs, 3032 KB]
   Test 6: TEST OK [0.000 secs, 3032 KB]
   Test 7: TEST OK [0.000 secs, 3032 KB]
   Test 8: TEST OK [0.000 secs, 3032 KB]
   Test 9: TEST OK [0.000 secs, 3032 KB]
   Test 10: TEST OK [0.000 secs, 3032 KB]
   Test 11: TEST OK [0.000 secs, 3032 KB]
   Test 12: TEST OK [0.000 secs, 3032 KB]
   Test 13: TEST OK [0.000 secs, 3032 KB]

All tests OK.
posted @ 2011-05-13 18:34  幻魇  阅读(278)  评论(0)  编辑  收藏  举报