1 #include <algorithm>
2 #include <cstdlib>
3 #include <numeric>
4 #include <iostream>
5 using namespace std;
6
7 int max(int i,int j)
8 {
9 if(i > j)
10 return i;
11 return j;
12 }
13
14 int main()
15 {
16 //freopen("acm.acm","r",stdin);
17 int dp[1005][31];
18 int tree[1005];
19 int T;
20 int W;
21 int i;
22 int j;
23 memset(dp,0,sizeof(dp));
24 cin>>T>>W;
25 for(i = 1;i <= T; ++ i)
26 cin>>tree[i];
27 for(i = 1; i <= T; ++ i)
28 {
29 dp[i][0] = dp[i-1][0];
30 if(tree[i] == 1)
31 ++ dp[i][0];
32 }
33 for(i = 1;i <= T;++ i)
34 {
35 for(j = 1;j <= W;++ j)
36 {
37 if(j > i)
38 break;
39 dp[i][j] = max(dp[i-1][j],dp[i-1][j-1]);
40 if(tree[i] == j%2+1)
41 ++ dp[i][j];
42 }
43 }
44 cout<<dp[T][W];
45 return 0;
46 }
