显示代码纯文本
- #include <cstdio>
- #include <cstring>
- #define file(x) "examfive." #x
- const int N = 12, V = 1 << 11 | 1;
- typedef long long ll;
- int n, m;
- ll f[N][V], fr;
- inline int set(int x, int p, int v) {
- if (v) return x | (1 << p - 1);
- else return x & ~(1 << p - 1);
- }
- inline int get(int x, int p) {return x >>(p - 1)&1;}
- void print(int x) {for (int i = 1; i <= m;i++, x>>=1) printf("%d", x&1);}
- void dfs(int r, int c, int s0, int s1) {
- // print(s0), putchar('\t'), print(s1), putchar('\n');
- if (c > m) {
- f[r + 1][s1] += fr;
- return;
- }
- if (get(s0, c) && get(s0, c + 1)) dfs(r, c + 2, s0, set(set(s1, c, 1), c + 1, 1));
- if (!get(s0, c)) dfs(r, c + 1, set(s0, c, 1), set(s1, c, 1));
- else dfs(r, c + 1, s0, s1);
- }
- void init(int c, int s) {
- if (c > m) f[1][s] = 1;
- else {
- if (c + 1 <= m) init(c + 2, set(set(s, c, 1), c + 1, 1));
- init(c + 1, s);
- }
- }
- int main() {
- // freopen("input", "r", stdin);
- freopen(file(in), "r", stdin);
- freopen(file(out), "w", stdout);
- while (scanf("%d%d", &n, &m)){
- if (n == 0 && m == 0) break;
- memset(f, 0, sizeof(f));
- init(1, 0);
- for (int i = 1; i < n; i++)
- for (int j = 0; j < 1 << m; j++)
- if (f[i][j]) fr = f[i][j], dfs(i, 1, j, 0);
- printf("%lld\n", f[n][(1 << m) - 1]);
- }
- }