Nice Sequence

Time Limit: 12000/6000MS (Java/Others)Memory Limit: 128000/64000KB (Java/Others)
 

Problem Description

      Let us consider the sequence a1, a2,..., an of non-negative integer numbers. Denote as ci,j the number of occurrences of the number i among a1,a2,..., aj. We call the sequence k-nice if for all i1<i2 and for all j the following condition is satisfied: ci1,j ≥ ci2,j −k. 

      Given the sequence a1,a2,..., an and the number k, find its longest prefix that is k-nice.

Input

      The first line of the input file contains n and k (1 ≤ n ≤ 200 000, 0 ≤ k ≤ 200 000). The second line contains n integer numbers ranging from 0 to n.

Output

      Output the greatest l such that the sequence a1, a2,..., al is k-nice.

Sample Input

10 1
0 1 1 0 2 2 1 2 2 3
2 0
1 0

Sample Output

8
0

Source

Andrew Stankevich Contest 23

Manager

 
解题:线段树。。。哎。。。当时不知怎么写复杂了。。。。真是蛋疼。。。。
 
Acdream 1427 Nice Sequence_iosAcdream 1427 Nice Sequence_#include_02
 1 #include <iostream>
 2 #include <cstdio>
 3 #include <cstring>
 4 #include <cmath>
 5 #include <algorithm>
 6 #include <climits>
 7 #include <vector>
 8 #include <queue>
 9 #include <cstdlib>
10 #include <string>
11 #include <set>
12 #include <stack>
13 #define LL long long
14 #define pii pair<int,int>
15 #define INF 0x3f3f3f3f
16 using namespace std;
17 const int maxn = 210000;
18 struct node{
19     int lt,rt,minv,maxv;
20 };
21 node tree[maxn<<2];
22 void build(int lt,int rt,int v){
23     tree[v].lt = lt;
24     tree[v].rt = rt;
25     tree[v].minv = tree[v].maxv = 0;
26     if(lt == rt) return;
27     int mid = (lt+rt)>>1;
28     build(lt,mid,v<<1);
29     build(mid+1,rt,v<<1|1);
30 }
31 void update(int k,int v,int &val){
32     if(tree[v].lt == tree[v].rt){
33         val = tree[v].maxv = ++tree[v].minv;
34         return;
35     }
36     int mid = (tree[v].lt + tree[v].rt)>>1;
37     if(k <= mid) update(k,v<<1,val);
38     else if(k > mid) update(k,v<<1|1,val);
39     tree[v].minv = min(tree[v<<1].minv,tree[v<<1|1].minv);
40     tree[v].maxv = max(tree[v<<1].maxv,tree[v<<1|1].maxv);
41 }
42 int query_min(int lt,int rt,int v){
43     if(tree[v].lt == lt && tree[v].rt == rt) return tree[v].minv;
44     int mid = (tree[v].lt + tree[v].rt)>>1;
45     if(rt <= mid) return query_min(lt,rt,v<<1);
46     else if(lt > mid) return query_min(lt,rt,v<<1|1);
47     else return min(query_min(lt,mid,v<<1),query_min(mid+1,rt,v<<1|1));
48 }
49 int query_max(int lt,int rt,int v){
50     if(tree[v].lt == lt && tree[v].rt == rt) return tree[v].maxv;
51     int mid = (tree[v].lt + tree[v].rt)>>1;
52     if(rt <= mid) return query_max(lt,rt,v<<1);
53     else if(lt > mid) return query_max(lt,rt,v<<1|1);
54     else return max(query_max(lt,mid,v<<1),query_max(mid+1,rt,v<<1|1));
55 }
56 int n,k,val,tmp,ans;
57 int main() {
58     while(~scanf("%d %d",&n,&k)){
59         build(0,n + 1,1);
60         ans = 0;
61         bool flag = true;
62         for(int i = 1; i <= n; i++){
63             scanf("%d",&tmp);
64             update(tmp,1,val);
65             if(flag && val <= query_min(0,tmp,1)+k && val >= query_max(tmp+1,n+1,1)-k) 
66                 ans = i;
67             else flag = false;
68         }
69         printf("%d\n",ans);
70     }
71     return 0;
72 }
View Code

 

zkw线段树

Acdream 1427 Nice Sequence_iosAcdream 1427 Nice Sequence_#include_02
 1 #include <iostream>
 2 #include <cstdio>
 3 #include <cstring>
 4 #include <cmath>
 5 #include <algorithm>
 6 #include <climits>
 7 #include <vector>
 8 #include <queue>
 9 #include <cstdlib>
10 #include <string>
11 #include <set>
12 #include <stack>
13 #define LL long long
14 #define pii pair<int,int>
15 #define INF 0x3f3f3f3f
16 using namespace std;
17 const int maxn = 200010;
18 int tree[maxn<<2][2],M;
19 void build(int n){
20     M = 1<<((int)log2(n)+2);
21 }
22 void update(int n,int &val){
23     ++tree[n += M][0];
24     val = tree[n][1] = tree[n][0];
25     for(n >>= 1; n; n >>= 1){
26         tree[n][0] = min(tree[n<<1][0],tree[n<<1|1][0]);
27         tree[n][1] = max(tree[n<<1][1],tree[n<<1|1][1]);
28     }
29 }
30 int query_min(int s,int t){
31     s += M - 1;
32     t += M + 1;
33     int minv = INF;
34     while(s^t^1){
35         if(~s&1) minv = min(minv,tree[s^1][0]);
36         if(t&1) minv = min(minv,tree[t^1][0]);
37         s >>= 1;
38         t >>= 1;
39     }
40     return minv;
41 }
42 int query_max(int s,int t){
43     s += M - 1;
44     t += M + 1;
45     int maxv = -1;
46     while(s^t^1){
47         if(~s&1) maxv = max(maxv,tree[s^1][1]);
48         if(t&1) maxv = max(maxv,tree[t^1][1]);
49         s >>= 1;
50         t >>= 1;
51     }
52     return maxv;
53 }
54 int main() {
55     int n,k,tmp,val,ans;
56     while(~scanf("%d %d",&n,&k)){
57         memset(tree,0,sizeof(tree));
58         build(n);
59         bool flag = true;
60         ans = 0;
61         for(int i = 1; i <= n; i++){
62             scanf("%d",&tmp);
63             update(tmp+1,val);
64             if(flag && val <= query_min(1,tmp+1)+k && val >= query_max(tmp+2,n+1)-k)
65                 ans = i;
66             else flag = false;
67         }
68         printf("%d\n",ans);
69     }
70     return 0;
71 }
View Code

 

快得不行了。。。

Acdream 1427 Nice Sequence_iosAcdream 1427 Nice Sequence_#include_02
 1 #include <iostream>
 2 #include <cstdio>
 3 #include <cstring>
 4 #include <cmath>
 5 #include <algorithm>
 6 #include <climits>
 7 #include <vector>
 8 #include <queue>
 9 #include <cstdlib>
10 #include <string>
11 #include <set>
12 #include <stack>
13 #define LL long long
14 #define pii pair<int,int>
15 #define INF 0x3f3f3f3f
16 using namespace std;
17 const int maxn = 200010;
18 int tree[maxn<<2] = {0},M;
19 int a[maxn] = {0};
20 void build(int n) {
21     M = 1<<((int)log2(n)+2);
22 }
23 void update(int n) {
24     ++tree[n += M];
25     for(n >>= 1; n; n >>= 1)
26         tree[n] = min(tree[n<<1],tree[n<<1|1]);
27 }
28 int query_min(int s,int t) {
29     s += M - 1;
30     t += M + 1;
31     int minv = INF;
32     while(s^t^1) {
33         if(~s&1) minv = min(minv,tree[s^1]);
34         if(t&1) minv = min(minv,tree[t^1]);
35         s >>= 1;
36         t >>= 1;
37     }
38     return minv;
39 }
40 void myscanf(int &x) {
41     char ch;
42     while((ch = getchar()) < '0' || ch > '9');
43     x = 0;
44     x = ch - '0';
45     while((ch = getchar()) >= '0' && ch <= '9')
46         x = x*10 + ch - '0';
47 }
48 int main() {
49     int n,k,tmp,ans;
50     scanf("%d %d",&n,&k);
51     build(n);
52     bool flag = true;
53     ans = 0;
54     for(int i = 1; i <= n; i++) {
55         myscanf(tmp);
56         if(flag) {
57             ++tmp;
58             ++a[tmp];
59             update(tmp);
60             if(query_min(1,tmp) < a[tmp] - k) flag = false;
61             if(flag) ans = i;
62         }
63     }
64     printf("%d\n",ans);
65     return 0;
66 }
View Code

 

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