CodeForcesGym 100517B Bubble Sort

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3 typedef long long LL;
 4 const int maxn = 100010;
 5 int c[maxn];
 6 void add(int i,int val) {
 7     while(i < maxn) {
 8         c[i] += val;
 9         i += i&-i;
10     }
11 }
12 int sum(int i,int ret = 0) {
13     while(i > 0) {
14         ret += c[i];
15         i -= i&-i;
16     }
17     return ret;
18 }
19 bool used[maxn];
20 int n,ans[maxn];
21 LL k;
22 LL check(int x) {
23     if(x < 0) return 0;
24     LL ret = 1;
25     for(int i = 0; i < x; ++i){
26         if(ret >= k) return ret;
27         ret <<= 1;
28     }
29     return ret;
30 }
31 int main() {
32 #define NAME "bubble"
33     freopen(NAME".in","r",stdin);
34     freopen(NAME".out","w",stdout);
35     while(scanf("%d%I64d",&n,&k),n||k) {
36         memset(used,false,sizeof used);
37         memset(c,0,sizeof c);
38         for(int i = 1; i <= n; ++i) add(i,1);
39         int cur = 1;
40         for(int i = 1; i < n; ++i) {
41             while(used[cur]) ++cur;
42             int big = sum(n) - sum(cur);
43             if(check(big-1) >= k) {
44                 ans[i] = cur;
45                 used[cur] = true;
46                 add(cur,-1);
47             } else {
48                 int t = cur + 1;
49                 k -= check(big-1);
50                 while(used[t]) ++t;
51                 int xx = sum(n) - sum(t);
52                 while(xx && check(xx-1) < k) {
53                     k -= check(xx-1);
54                     ++t;
55                     while(used[t]) ++t;
56                     xx = sum(n) - sum(t);
57                 }
58                 used[t] = true;
59                 ans[i] = t;
60                 add(t,-1);
61             }
62         }
63         for(int i = 1; i <= n; ++i)
64             if(!used[i]) {
65                 ans[n] = i;
66                 break;
67             }
68         for(int i = 1; i <= n; ++i)
69             printf("%d%c",ans[i],i==n?‘\n‘:‘ ‘);
70     }
71     return 0;
72 }
73 /*
74 1 2 3 4 5
75 1 2 3 5 4
76 1 2 4 3 5
77 1 2 5 3 4
78 1 3 2 4 5
79 1 3 2 5 4
80 1 4 2 3 5
81 1 5 2 3 4
82 2 1 3 4 5
83 2 1 3 5 4
84 2 1 4 3 5
85 2 1 5 3 4
86 3 1 2 4 5
87 3 1 2 5 4
88 4 1 2 3 5
89 5 1 2 3 4
90 */