1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 #include #include #include #include #include typedef unsigned long long int llu; static const int MAX_N = 3000; static const llu MODULO_BY = 1000 * 1000 * 1000 + 7; bool matrix[MAX_N][MAX_N]; bool ones[MAX_N][MAX_N]; uint8_t twos[MAX_N][MAX_N]; llu ones_count; llu twos_sum; int n, k; llu solve_one(); llu solve_two(); llu solve_three(); llu solve_four(); inline llu safe_mul(llu a, llu b) { return (a * b) % MODULO_BY; } llu safe_mul_div(std::vector noms, std::vector denoms) { llu ret = 1; for (llu nom : noms) { int i = 0; while (i < denoms.size()) { const llu denom = denoms[i]; if (nom % denom == 0) { nom /= denom; denoms.erase(denoms.begin() + i); } else { i++; } } ret = safe_mul(ret, nom); } assert(denoms.empty()); return ret; } llu safe_count_tuples(llu n, llu k) { std::vector noms, denoms; for (llu i = 0; i < k; i++) { noms.push_back(n - i); denoms.push_back(k - i); } return safe_mul_div(std::move(noms), std::move(denoms)); } void read_data() { scanf("%d %d", &n, &k); for (int y = 0; y < n; y++) { for (int x = 0; x < n; x++) { int c = getchar(); while (c != '#' && c != '.') { c = getchar(); } matrix[y][x] = (c == '#'); } } } inline bool is_ones(int x, int y) { if (x < 0 || y < 0 || x >= n || y >= n) { return false; } return ones[y][x]; } inline uint8_t get_twos(int x, int y) { if (x < 0 || y < 0 || x >= n || y >= n) { return 0; } return twos[y][x]; } llu solve_one() { // That's easy! return ones_count; } llu solve_two() { // Two cases: // 1. Two tiles lie next to already placed tiles // 2. One of the tiles is a "two", second is a "one" return (safe_count_tuples(ones_count, 2) + twos_sum) % MODULO_BY; } llu solve_three() { // Four cases this time: // 1. All three tiles are "ones" llu ret = safe_count_tuples(ones_count, 3); // 2. One tile is a "two", with two "ones" adjacent // 3. One tile is a "two", second is a "one", third is also a "one" but not adjacent // 4. One tile is a "two", second is a "one", third is something else (but adjacent) llu count = 0; for (int y = 0; y < n; y++) { for (int x = 0; x < n; x++) { // Case 2 count += (llu)(twos[y][x] * (twos[y][x] - 1) / 2); // Case 3 count += (llu)(twos[y][x] * (ones_count - twos[y][x])); // Case 4 const uint8_t unclassified = ((x <= 0 || (!ones[y][x - 1] && twos[y][x - 1] == 0)) ? 1 : 0) + ((x >= n - 1 || (!ones[y][x + 1] && twos[y][x + 1] == 0)) ? 1 : 0) + ((y <= 0 || (!ones[y - 1][x] && twos[y - 1][x] == 0)) ? 1 : 0) + ((y >= n - 1 || (!ones[y + 1][x] && twos[y + 1][x] == 0)) ? 1 : 0); count += (llu)(twos[y][x] * unclassified); count %= MODULO_BY; } } return (ret + count) % MODULO_BY; } llu solve_four() { // 1: All four tiles are "ones" llu ret = safe_count_tuples(ones_count, 4); // 2: One tile is a "two", three "ones" are adjacent // 3: two "ones" are adjacent, last tile is something else, but adjacent // 4: last tile is a non-adjacent "one" // 5: one "one" is adjacent, two tiles are something else, but adjacent // 6: one tile is an adjacent "one", last is adjacent something-else // 7: two tiles are something-else return 0; } llu count() { // Place "ones" llu count = 0; for (int y = 0; y < n; y++) { for (int x = 0; x < n; x++) { if (matrix[y][x]) { continue; } ones[y][x] = (x > 0 && matrix[y][x - 1]) || (x < n - 1 && matrix[y][x + 1]) || (y > 0 && matrix[y - 1][x]) || (y < n - 1 && matrix[y + 1][x]); if (ones[y][x]) { count++; } } } ones_count = count; // Place "twos" count = 0; for (int y = 0; y < n; y++) { for (int x = 0; x < n; x++) { if (matrix[y][x] || ones[y][x]) { continue; } twos[y][x] = ((x > 0 && ones[y][x - 1]) ? 1 : 0) + ((x < n - 1 && ones[y][x + 1]) ? 1 : 0) + ((y > 0 && ones[y - 1][x]) ? 1 : 0) + ((y < n - 1 && ones[y + 1][x]) ? 1 : 0); count += (llu)twos[y][x]; } } twos_sum = count; if (k == 1) { return solve_one(); } else if (k == 2) { return solve_two(); } else if (k == 3) { return solve_three(); } /*else if (k == 4) { return solve_four(); }*/ puts("MACHINE BROKE"); return 0; } int main() { read_data(); const llu result = count(); printf("%llu\n", result); return 0; }