P1357-花园 

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3 typedef long long ll;
 4 typedef double db;
 5 #define INF 0x3f3f3f3f
 6 #define _for(i,a,b) for(int i = (a);i < b;i ++)
 7 #define _rep(i,a,b) for(int i = (a);i > b;i --)
 8 
 9 inline ll read()
10 {
11     ll ans = 0;
12     char ch = getchar(), last = ' ';
13     while(!isdigit(ch)) last = ch, ch = getchar();
14     while(isdigit(ch)) ans = (ans << 1) + (ans << 3) + ch - '0', ch = getchar();
15     if(last == '-') ans = -ans;
16     return ans;
17 }
18 inline void write(ll x)
19 {
20     if(x < 0) x = -x, putchar('-');
21     if(x >= 10) write(x / 10);
22     putchar(x % 10 + '0');
23 }
24 ll N,M,K;
25 ll cnt,ans;
26 ll dp[1<<5],a[1<<5][1<<5];
27 bool pd[1<<5];
28 void mul1(ll a[1<<5][1<<5])
29 {
30     ll c[1<<5][1<<5];
31     memset(c,0,sizeof(c));
32     _for(i,0,1<<5)
33         _for(j,0,1<<5)
34             _for(k,0,1<<5)
35                 c[i][j] = (c[i][j] + a[i][k] * a[k][j]) % 1000000007;
36     memmove(a,c,sizeof(c));
37 }
38 void mul2(ll dp[1<<5], ll a[1<<5][1<<5])
39 {
40     ll c[1<<5];
41     memset(c,0,sizeof(c));
42     _for(j,0,1<<5)
43         _for(k,0,1<<5)
44             c[j] = (c[j] + dp[k] * a[k][j]) % 1000000007;
45     memmove(dp,c,sizeof(c));
46 }
47 int main()
48 {
49     N = read(), M = read(), K = read();
50     _for(i,0,1<<M)
51     {
52         cnt = 0;
53         _for(j,0,M+1)
54         if(i & (1 << j))
55             cnt ++;
56         if(cnt <= K)
57             pd[i] = true;
58     }
59 
60     _for(i,0,1<<M)
61     {
62         if(pd[i])
63         {
64             memset(dp,0,sizeof(dp));
65             memset(a,0,sizeof(a));
66             dp[i] = 1;
67             _for(j,0,1<<M)
68             if(pd[j])
69             {
70                 a[j>>1][j] = 1;
71                 a[(j>>1)+(1<<(M-1))][j] = 1;
72             }
73             for(ll y = N; y ; y >>= 1,mul1(a))
74                 if(y & 0x1)
75                     mul2(dp,a);
76             ans = (ans+dp[i])%1000000007;
77         }
78     }
79     write(ans);
80     return 0;
81 }

 

posted @ 2019-09-06 11:17  Asurudo  阅读(184)  评论(0)    收藏  举报