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| | 1 | |
| | 2 | import static utils.Utils.*; |
| | 3 | |
| | 4 | import java.io.OutputStreamWriter; |
| | 5 | import java.io.BufferedWriter; |
| | 6 | import java.util.Comparator; |
| | 7 | import java.io.OutputStream; |
| | 8 | import java.io.PrintWriter; |
| | 9 | import java.io.Writer; |
| | 10 | import java.util.List; |
| | 11 | import java.io.IOException; |
| | 12 | import java.util.Arrays; |
| | 13 | import java.util.InputMismatchException; |
| | 14 | import java.util.ArrayList; |
| | 15 | import java.util.NoSuchElementException; |
| | 16 | import java.math.BigInteger; |
| | 17 | import java.io.InputStream; |
| | 18 | |
| | 19 | /// This test is based on Egor Kulikov task solution from |
| | 20 | /// http://codeforces.com/submissions/Egor |
| | 21 | /// http://codeforces.com/problemset/problem/336/E |
| | 22 | |
| | 23 | /** |
| | 24 | * Built using CHelper plug-in |
| | 25 | * Actual solution is at the top |
| | 26 | * @author Egor Kulikov (egor@egork.net) |
| | 27 | */ |
| | 28 | public class EgorTask1Test { |
| | 29 | public static void main(String[] args) { |
| | 30 | InputStream inputStream = System.in; |
| | 31 | OutputStream outputStream = System.out; |
| | 32 | InputReader in = new InputReader(inputStream); |
| | 33 | OutputWriter out = new OutputWriter(outputStream); |
| | 34 | TaskE solver = new TaskE(); |
| | 35 | solver.solve(1, in, out); |
| | 36 | out.close(); |
| | 37 | } |
| | 38 | } |
| | 39 | |
| | 40 | class TaskE { |
| | 41 | static final long MOD = 1000000007; |
| | 42 | |
| | 43 | long[][][] result; |
| | 44 | long[][][] resultSmall; |
| | 45 | long[][] c = IntegerUtils.generateBinomialCoefficients(13); |
| | 46 | |
| | 47 | public void solve(int testNumber, InputReader in, OutputWriter out) { |
| | 48 | int size = in.readInt(); |
| | 49 | int count = in.readInt(); |
| | 50 | result = new long[size + 1][count + 1][16]; |
| | 51 | resultSmall = new long[size + 1][count + 1][16]; |
| | 52 | ArrayUtils.fill(result, -1); |
| | 53 | ArrayUtils.fill(resultSmall, -1); |
| | 54 | long answer = calculate(size, count, 0); |
| | 55 | answer *= IntegerUtils.factorial(count, MOD); |
| | 56 | answer %= MOD; |
| | 57 | out.printLine(answer); |
| | 58 | } |
| | 59 | |
| | 60 | private long calculate(int size, int count, int mask) { |
| | 61 | if (count < 0) |
| | 62 | return 0; |
| | 63 | if (result[size][count][mask] != -1) |
| | 64 | return result[size][count][mask]; |
| | 65 | long current = 0; |
| | 66 | if (mask == 0) |
| | 67 | current += 2 * calculate(0, count - 2, 15); |
| | 68 | for (int i = 0; i < 4; i++) { |
| | 69 | int j = (i + 1) & 3; |
| | 70 | if ((mask >> i & 1) != 0 || (mask >> j & 1) != 0) |
| | 71 | continue; |
| | 72 | int remaining = 15 - mask - (1 << i) - (1 << j); |
| | 73 | for (int k = remaining; ; k = (k - 1) & remaining) { |
| | 74 | current += calculateSmall(size, count - 1 - Integer.bitCount(k), mask + (1 << i) + (1 << j) + k); |
| | 75 | if (k == 0) |
| | 76 | break; |
| | 77 | } |
| | 78 | } |
| | 79 | int remaining = 15 - mask; |
| | 80 | for (int k = remaining; ; k = (k - 1) & remaining) { |
| | 81 | current += calculateSmall(size, count - Integer.bitCount(k), mask + k); |
| | 82 | if (k == 0) |
| | 83 | break; |
| | 84 | } |
| | 85 | return result[size][count][mask] = current % MOD; |
| | 86 | } |
| | 87 | |
| | 88 | private long calculateSmall(int size, int count, int mask) { |
| | 89 | if (count < 0) |
| | 90 | return 0; |
| | 91 | if (resultSmall[size][count][mask] != -1) |
| | 92 | return resultSmall[size][count][mask]; |
| | 93 | if (size == 0) |
| | 94 | return resultSmall[size][count][mask] = count == 0 ? 1 : 0; |
| | 95 | int max = 3 * Integer.bitCount(15 - mask); |
| | 96 | int pairCount = 0; |
| | 97 | for (int i = 0; i < 4; i++) { |
| | 98 | int j = (i + 1) & 3; |
| | 99 | if ((mask >> i & 1) == 0 && ((mask >> j & 1) == 0)) |
| | 100 | pairCount++; |
| | 101 | } |
| | 102 | long current = 0; |
| | 103 | for (int j = 0; j <= pairCount; j++) { |
| | 104 | for (int i = 0; i <= max - 2 * j; i++) |
| | 105 | current += calculate(size - 1, count - i - j, mask) * c[max - 2 * j][i] * c[pairCount][j]; |
| | 106 | } |
| | 107 | return resultSmall[size][count][mask] = current % MOD; |
| | 108 | } |
| | 109 | } |
| | 110 | |
| | 111 | class IntegerUtils { |
| | 112 | |
| | 113 | public static long[][] generateBinomialCoefficients(int n) { |
| | 114 | long[][] result = new long[n + 1][n + 1]; |
| | 115 | for (int i = 0; i <= n; i++) { |
| | 116 | result[i][0] = 1; |
| | 117 | for (int j = 1; j <= i; j++) |
| | 118 | result[i][j] = result[i - 1][j - 1] + result[i - 1][j]; |
| | 119 | } |
| | 120 | return result; |
| | 121 | } |
| | 122 | |
| | 123 | public static long factorial(int n, long mod) { |
| | 124 | long result = 1; |
| | 125 | for (int i = 2; i <= n; i++) |
| | 126 | result = result * i % mod; |
| | 127 | return result % mod; |
| | 128 | } |
| | 129 | |
| | 130 | } |
| | 131 | |
| | 132 | class InputReader { |
| | 133 | |
| | 134 | private InputStream stream; |
| | 135 | private byte[] buf = new byte[1024]; |
| | 136 | private int curChar; |
| | 137 | private int numChars; |
| | 138 | private SpaceCharFilter filter; |
| | 139 | |
| | 140 | public InputReader(InputStream stream) { |
| | 141 | this.stream = stream; |
| | 142 | } |
| | 143 | |
| | 144 | public int read() { |
| | 145 | if (numChars == -1) |
| | 146 | throw new InputMismatchException(); |
| | 147 | if (curChar >= numChars) { |
| | 148 | curChar = 0; |
| | 149 | try { |
| | 150 | numChars = stream.read(buf); |
| | 151 | } catch (IOException e) { |
| | 152 | throw new InputMismatchException(); |
| | 153 | } |
| | 154 | if (numChars <= 0) |
| | 155 | return -1; |
| | 156 | } |
| | 157 | return buf[curChar++]; |
| | 158 | } |
| | 159 | |
| | 160 | public int readInt() { |
| | 161 | int c = read(); |
| | 162 | while (isSpaceChar(c)) |
| | 163 | c = read(); |
| | 164 | int sgn = 1; |
| | 165 | if (c == '-') { |
| | 166 | sgn = -1; |
| | 167 | c = read(); |
| | 168 | } |
| | 169 | int res = 0; |
| | 170 | do { |
| | 171 | if (c < '0' || c > '9') |
| | 172 | throw new InputMismatchException(); |
| | 173 | res *= 10; |
| | 174 | res += c - '0'; |
| | 175 | c = read(); |
| | 176 | } while (!isSpaceChar(c)); |
| | 177 | return res * sgn; |
| | 178 | } |
| | 179 | |
| | 180 | public boolean isSpaceChar(int c) { |
| | 181 | if (filter != null) |
| | 182 | return filter.isSpaceChar(c); |
| | 183 | return isWhitespace(c); |
| | 184 | } |
| | 185 | |
| | 186 | public static boolean isWhitespace(int c) { |
| | 187 | return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1; |
| | 188 | } |
| | 189 | |
| | 190 | public interface SpaceCharFilter { |
| | 191 | public boolean isSpaceChar(int ch); |
| | 192 | } |
| | 193 | } |
| | 194 | |
| | 195 | class OutputWriter { |
| | 196 | private final PrintWriter writer; |
| | 197 | |
| | 198 | public OutputWriter(OutputStream outputStream) { |
| | 199 | writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream))); |
| | 200 | } |
| | 201 | |
| | 202 | public OutputWriter(Writer writer) { |
| | 203 | this.writer = new PrintWriter(writer); |
| | 204 | } |
| | 205 | |
| | 206 | public void print(Object...objects) { |
| | 207 | for (int i = 0; i < objects.length; i++) { |
| | 208 | if (i != 0) |
| | 209 | writer.print(' '); |
| | 210 | writer.print(objects[i]); |
| | 211 | } |
| | 212 | } |
| | 213 | |
| | 214 | public void printLine(Object...objects) { |
| | 215 | print(objects); |
| | 216 | writer.println(); |
| | 217 | } |
| | 218 | |
| | 219 | public void close() { |
| | 220 | writer.close(); |
| | 221 | } |
| | 222 | |
| | 223 | } |
| | 224 | |
| | 225 | class ArrayUtils { |
| | 226 | |
| | 227 | public static void fill(long[][] array, long value) { |
| | 228 | for (long[] row : array) |
| | 229 | Arrays.fill(row, value); |
| | 230 | } |
| | 231 | |
| | 232 | public static void fill(long[][][] array, long value) { |
| | 233 | for (long[][] row : array) |
| | 234 | fill(row, value); |
| | 235 | } |
| | 236 | |
| | 237 | } |