1 #include <bits/stdc++.h> 2 #define _for(i,a,b) for(register int i = (a);i < b;i ++) 3 #define _rep(i,a,b) for(register int i = (a);i > b;i --) 4 #define INF 0x3f3f3f3f 5 #define MOD 1000000007 6 #define maxn 15003 7 typedef long long ll; 8 9 using namespace std; 10 typedef pair<int,int> P; 11 inline ll read() 12 { 13 ll ans = 0; 14 char ch = getchar(), last = ' '; 15 while(!isdigit(ch)) last = ch, ch = getchar(); 16 while(isdigit(ch)) ans = (ans << 1) + (ans << 3) + ch - '0', ch = getchar(); 17 if(last == '-') ans = -ans; 18 return ans; 19 } 20 inline void write(ll x) 21 { 22 if(x < 0) x = -x, putchar('-'); 23 if(x >= 10) write(x / 10); 24 putchar(x % 10 + '0'); 25 } 26 int N,K; 27 int validState[maxn],validStateKingNum[maxn]; 28 int validNum = 0; 29 ll dp[10][maxn][82]; 30 void Init(int curValidState,int curValidStateKingNum,int col) 31 { 32 if(col > N-1) 33 { 34 validState[++validNum] = curValidState; 35 validStateKingNum[validNum] = curValidStateKingNum; 36 return ; 37 } 38 Init(curValidState,curValidStateKingNum,col + 1); 39 Init(curValidState + (1<<col),curValidStateKingNum + 1,col + 2); 40 } 41 int main() 42 { 43 N = read();K = read(); 44 Init(0,0,0); 45 _for(i,1,validNum+1) 46 dp[1][i][validStateKingNum[i]] = 1; 47 _for(i,2,N+1) 48 _for(j,1,validNum+1) 49 _for(k,1,validNum+1) 50 { 51 if(validState[j]&validState[k] 52 ||(validState[j]<<1)&validState[k] 53 ||(validState[j]&validState[k]<<1)) 54 continue; 55 _rep(s,K,validStateKingNum[j]-1) 56 dp[i][j][s] += dp[i-1][k][s-validStateKingNum[j]]; 57 } 58 ll rnt = 0; 59 _for(i,1,validNum+1) 60 rnt += dp[N][i][K]; 61 write(rnt); 62 return 0; 63 }