BZOJ4007 [JLOI2015]战争调度

 1 /**************************************************************
 2     Problem: 4007
 3     User: rausen
 4     Language: C++
 5     Result: Accepted
 6     Time:240 ms
 7     Memory:13216 kb
 8 ****************************************************************/
 9  
10 #include <cstdio>
11 #include <cstring>
12 #include <algorithm>
13  
14 using namespace std;
15 const int N = (1 << 10) + 5;
16  
17 int n, m, ans;
18 int a[N][N], b[N][N], f[N][N];
19 int now[N];
20  
21 inline int read();
22  
23 #define ls p << 1
24 #define rs p << 1 | 1
25 void dfs(int p, int sz) {
26     int i, j, mnl, mxl, tot;
27     if (sz == 1) {
28         f[p][0] = f[p][1] = 0;
29         for (i = p >> 1; i; i >>= 1)
30             if (now[i] == 0) f[p][1] += a[p][i];
31             else f[p][0] += b[p][i];
32         return;
33     }
34     tot = min(sz, m);
35     memset(f[p], 0, sizeof(f[0][0]) * (tot + 1));
36     now[p] = 0;
37     dfs(ls, sz >> 1), dfs(rs, sz >> 1);
38     for (i = 0; i <= tot; ++i) {
39         mnl = max(i - (sz >> 1), 0), mxl = min(sz >> 1, i);
40         for (j = mnl; j <= mxl; ++j)
41             f[p][i] = max(f[p][i], f[ls][j] + f[rs][i - j]);
42     }
43      
44     now[p] = 1;
45     dfs(ls, sz >> 1), dfs(rs, sz >> 1);
46     for (i = 0; i <= tot; ++i) {
47         mnl = max(i - (sz >> 1), 0), mxl = min(sz >> 1, i);
48         for (j = mnl; j <= mxl; ++j)
49             f[p][i] = max(f[p][i], f[ls][j] + f[rs][i - j]);
50     }   
51 }
52 #undef ls
53 #undef rs
54  
55 int main() {
56     int i, j;
57     n = read(), m = read();
58     for (i = 1 << n - 1; i < 1 << n; ++i)
59         for (j = i >> 1; j; j >>= 1)
60             a[i][j] = read();
61     for (i = 1 << n - 1; i < 1 << n; ++i)
62         for (j = i >> 1; j; j >>= 1)
63             b[i][j] = read();
64     dfs(1, 1 << n - 1);
65     for (ans = i = 0; i <= m; ++i)
66         ans = max(ans, f[1][i]);
67     printf("%d\n", ans);
68     return 0;
69 }
70  
71 inline int read() {
72     static int x;
73     static char ch;
74     x = 0, ch = getchar();
75     while (ch < ‘0‘ || ‘9‘ < ch)
76         ch = getchar();
77     while (‘0‘ <= ch && ch <= ‘9‘) {
78         x = x * 10 + ch - ‘0‘;
79         ch = getchar();
80     }
81     return x;
82 }