#include <bitset> #include <cassert> #include <cstdio> #include <cstdlib> #include <iostream> #include <vector> using namespace std; class BigNumber { public: BigNumber() : v_(1, 0) {} BigNumber(const int n) : v_(1, n) {} /* void Print() const { cerr << v_.back(); for (int i = v_.size() - 2; i >= 0; --i) { const long long a = v_[i] ? v_[i] : 1; long long b = kBlock / 10; while (a < b) { cerr << '0'; b /= 10; } cerr << v_[i]; } cerr << endl; } */ void Printf() const { printf("%lld", v_.back()); for (int i = v_.size() - 2; i >= 0; --i) { const long long a = v_[i] ? v_[i] : 1; long long b = kBlock / 10; while (a < b) { printf("0"); b /= 10; } printf("%lld", v_[i]); } printf("\n"); } BigNumber operator/(const int n) const { BigNumber ret = *this; ret /= n; return ret; } BigNumber operator+(const int n) const { BigNumber ret = *this; ret += n; return ret; } BigNumber operator*(const int n) const { BigNumber ret = *this; ret *= n; return ret; } BigNumber operator/=(const int n) { long long carry = 0; for (int i = v_.size() - 1; i >= 0; --i) { long long a = v_[i] + carry; carry = (a % n) * kBlock; v_[i] = a / n; } CutLeadingZeros(); return *this; } BigNumber operator+=(const BigNumber& n) { long long carry = 0; int i = 0; while (carry || i < n.v_.size()) { if (i >= v_.size()) v_.push_back(0); long long a = v_[i] + carry; if (i < n.v_.size()) a += n.v_[i]; carry = a / kBlock; v_[i] = a % kBlock; ++i; } return *this; } BigNumber operator+=(const int n) { long long carry = 0; for (int i = 0; i < v_.size(); ++i) { long long a = v_[i] + n + carry; carry = a / kBlock; v_[i] = a % kBlock; } if (carry) v_.push_back(carry); return *this; } BigNumber operator*=(const int n) { long long carry = 0; for (int i = 0; i < v_.size(); ++i) { long long a = v_[i] * n + carry; carry = a / kBlock; v_[i] = a % kBlock; } if (carry) v_.push_back(carry); return *this; } int operator%(const int n) const { // cerr << '%' << n << endl; // cerr << v_.size() << endl; long long ret = 0; long long delta = 1; for (int i = 0; i < v_.size(); ++i) { // cerr << v_[i] << endl; ret += (delta * v_[i]) % n; ret %= n; delta *= kBlock; delta %= n; } // cerr << ret << endl; return ret; } bool operator!=(const BigNumber& rhs) const { return v_ != rhs.v_; } bool operator==(const int n) const { return v_.size() == 1 && v_[0] == n; } private: void CutLeadingZeros() { while (v_.size() > 1 && v_.back() == 0) v_.resize(v_.size() - 1); } static const long long kBlock = 1000LL * 1000LL * 1000LL * 1000LL * 1000LL; vector<long long> v_; }; // 24 0.2/1.0s // 27 TLE const int kBrute = 1 << 24; const int kMaxN = 200; const int kInfinity = kMaxN + 1; bitset<kMaxN> bad; bitset<kMaxN> robots; int n; BigNumber power; BigNumber shift(0); BigNumber step(1); vector<bitset<kMaxN> > can, can_power; vector<bitset<kMaxN> > Multiply(const vector<bitset<kMaxN> >& a, const vector<bitset<kMaxN> >& b) { vector<bitset<kMaxN> > ret(n); for (int i = 0; i < n; ++i) for (int j = 0; j < n; ++j) if (a[i].test(j)) ret[i] |= b[j]; return ret; } vector<bitset<kMaxN> > Power(const vector<bitset<kMaxN> >& b, BigNumber exp) { /* cerr << "Computing power "; exp.Print(); */ if (exp == 1) return b; vector<bitset<kMaxN> > half = Power(b, exp / 2); vector<bitset<kMaxN> > full = Multiply(half, half); if (exp % 2) return Multiply(full, b); else return full; } void CheckAndAdvance() { if ((robots & bad).none()) { shift.Printf(); exit(0); } /* cerr << "Advancing "; step.Print(); cerr << "Power is "; power.Print(); */ if (power != step) { can_power = Power(can, step); power = step; } bitset<kMaxN> robots_new; // cerr << "can_power size " << can_power.size() << endl; for (int j = 0; j < n; ++j) if (robots.test(j)) robots_new |= can_power[j]; robots = robots_new; // cerr << "Increasing shift." << endl; shift += step; /* cerr << "New shift " << flush; shift.Print(); */ } long long Gcd(long long a, long long b) { // cerr << "Gcd " << a << ' ' << b << endl; while (true) { if (!a) return b; b %= a; if (!b) return a; a %= b; } } long long Gcd(const BigNumber& a, const long long b) { assert(b != 0); return Gcd(a % b, b); } BigNumber Lcm(const BigNumber& a, const long long b) { return a * (b / Gcd(a, b)); } long long Lcm(const long long a, const long long b) { return a * (b / Gcd(a, b)); } int main() { int b; int r; scanf("%d%d%d", &n, &b, &r); can.resize(n); for (int i = 0; i < n; ++i) for (int j = 0; j < n; ++j) { char c; do { scanf("%c", &c); } while (c != '0' && c != '1'); if (c == '1') can[i].set(j); } power = 1; can_power = can; for (int i = 0; i < r; ++i) { int robot; scanf("%d", &robot); robots.set(robot - 1); } for (int i = b; i < n; ++i) bad.set(i); /* const int brute_limit = kBrute / n; for (int i = 0; i < brute_limit; ++i) { } printf("-1\n"); */ vector<vector<pair<int, int> > > dist(n, vector<pair<int, int> >(n, make_pair(kInfinity, kInfinity))); for (int i = 0; i < n; ++i) for (int j = 0; j < n; ++j) if (can[i][j]) dist[i][j] = make_pair(1, kInfinity); { bool change = true; while (change) { change = false; for (int i = 0; i < n; ++i) for (int j = 0; j < n; ++j) for (int k = 0; k < n; ++k) { pair<int, int> better = make_pair(dist[j][i].first + dist[i][k].first, min(dist[j][i].second, dist[i][k].second)); if (j == i && dist[j][i].first < kInfinity) better = min(better, make_pair(dist[i][k].first, dist[j][i].first)); if (i == k && dist[i][k].first < kInfinity) better = min(better, make_pair(dist[j][i].first, dist[i][k].first)); if (better < dist[j][k]) { dist[j][k] = better; change = true; } } } } /* for (int i = 0; i < n; ++i) { for (int j = 0; j < n; ++j) { if (dist[i][j].first == kInfinity) cerr << "- "; else cerr << dist[i][j].first << ',' << dist[i][j].second << ' '; } cerr << endl; } */ vector<vector<bool> > avoid(n + 1); for (int i = 1; i <= n; ++i) avoid[i].resize(i); for (int i = n - 1; i >= b; --i) { int max_reach = robots.test(i) ? 0 : kInfinity; for (int j = 0; j < n; ++j) if (robots.test(j)) if (dist[j][i].first < kInfinity) if (max_reach == kInfinity || dist[j][i].first > max_reach) max_reach = dist[j][i].first; // If max_reach == kInfinity, we can simply forget about this guy. if (max_reach < kInfinity) { // cerr << "Max reach: " << max_reach << endl; // Just store the congruences (slighly bluffy here). for (int j = 0; j < n; ++j) if (robots.test(j)) { const int distance = dist[j][i].first; if (distance < kInfinity) { const int period = dist[j][i].second; if (period < kInfinity) { avoid[period][(shift + distance) % period] = true; // cerr << i << ": avoid " << period << ' ' << (shift + distance) % period << endl; } } } // We can simply forward time and then forget about this guy. while (max_reach-- >= 0) CheckAndAdvance(); } } // Now we just need to satisfy the congruences. { bool change = true; while (change) { change = false; for (int i = 1; i <= n; ++i) for (int j = 0; j < i; ++j) for (int k = i; k <= n; k += i) { bool all_avoid = true; for (int l = j; l < k; l += i) all_avoid &= avoid[k][l]; if (avoid[i][j] != all_avoid) { change = true; if (all_avoid) avoid[i][j] = true; else for (int l = j; l < k; l += i) avoid[k][l] = true; } } } } for (int i = 1; i <= n; ++i) { bool contradiction = true; for (int j = 0; j < i; ++j) { // if (avoid[i][j]) cerr << "Avoid " << i << ' ' << j << endl; contradiction &= avoid[i][j]; } if (contradiction) { printf("-1\n"); return 0; } } step = 1; vector<int> choice(n + 1, -1); for (int i = n; i >= 1; --i) { // cerr << "Checking modulo " << i << endl; if (choice[i] != -1) { if (shift % i != choice[i]) { cerr << "Choice mismatch." << endl; printf("-1\n"); return 0; } } else { bool freedom = true; for (int j = 0; j < i; ++j) if (avoid[i][j]) freedom = false; if (!freedom) { for (int j = 0; j < i; ++j) if (avoid[i][shift % i]) CheckAndAdvance(); else break; if (avoid[i][shift % i]) { cerr << "This should have been detected earlier." << endl; printf("-1\n"); return 0; } /* shift.Print(); cerr << "Remainder by " << i << " is " << shift % i << endl; */ for (int j = 1; j <= i; ++j) if (i % j == 0) choice[j] = shift % j; /* cerr << "Old step "; step.Print(); cerr << "Computing LCM with " << i << endl; */ step = Lcm(step, i); /* cerr << "New step "; step.Print(); */ } } } CheckAndAdvance(); cerr << "This shouldn't be happenning, really." << endl; printf("-1\n"); // shift.Printf(); return 0; }
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 | #include <bitset> #include <cassert> #include <cstdio> #include <cstdlib> #include <iostream> #include <vector> using namespace std; class BigNumber { public: BigNumber() : v_(1, 0) {} BigNumber(const int n) : v_(1, n) {} /* void Print() const { cerr << v_.back(); for (int i = v_.size() - 2; i >= 0; --i) { const long long a = v_[i] ? v_[i] : 1; long long b = kBlock / 10; while (a < b) { cerr << '0'; b /= 10; } cerr << v_[i]; } cerr << endl; } */ void Printf() const { printf("%lld", v_.back()); for (int i = v_.size() - 2; i >= 0; --i) { const long long a = v_[i] ? v_[i] : 1; long long b = kBlock / 10; while (a < b) { printf("0"); b /= 10; } printf("%lld", v_[i]); } printf("\n"); } BigNumber operator/(const int n) const { BigNumber ret = *this; ret /= n; return ret; } BigNumber operator+(const int n) const { BigNumber ret = *this; ret += n; return ret; } BigNumber operator*(const int n) const { BigNumber ret = *this; ret *= n; return ret; } BigNumber operator/=(const int n) { long long carry = 0; for (int i = v_.size() - 1; i >= 0; --i) { long long a = v_[i] + carry; carry = (a % n) * kBlock; v_[i] = a / n; } CutLeadingZeros(); return *this; } BigNumber operator+=(const BigNumber& n) { long long carry = 0; int i = 0; while (carry || i < n.v_.size()) { if (i >= v_.size()) v_.push_back(0); long long a = v_[i] + carry; if (i < n.v_.size()) a += n.v_[i]; carry = a / kBlock; v_[i] = a % kBlock; ++i; } return *this; } BigNumber operator+=(const int n) { long long carry = 0; for (int i = 0; i < v_.size(); ++i) { long long a = v_[i] + n + carry; carry = a / kBlock; v_[i] = a % kBlock; } if (carry) v_.push_back(carry); return *this; } BigNumber operator*=(const int n) { long long carry = 0; for (int i = 0; i < v_.size(); ++i) { long long a = v_[i] * n + carry; carry = a / kBlock; v_[i] = a % kBlock; } if (carry) v_.push_back(carry); return *this; } int operator%(const int n) const { // cerr << '%' << n << endl; // cerr << v_.size() << endl; long long ret = 0; long long delta = 1; for (int i = 0; i < v_.size(); ++i) { // cerr << v_[i] << endl; ret += (delta * v_[i]) % n; ret %= n; delta *= kBlock; delta %= n; } // cerr << ret << endl; return ret; } bool operator!=(const BigNumber& rhs) const { return v_ != rhs.v_; } bool operator==(const int n) const { return v_.size() == 1 && v_[0] == n; } private: void CutLeadingZeros() { while (v_.size() > 1 && v_.back() == 0) v_.resize(v_.size() - 1); } static const long long kBlock = 1000LL * 1000LL * 1000LL * 1000LL * 1000LL; vector<long long> v_; }; // 24 0.2/1.0s // 27 TLE const int kBrute = 1 << 24; const int kMaxN = 200; const int kInfinity = kMaxN + 1; bitset<kMaxN> bad; bitset<kMaxN> robots; int n; BigNumber power; BigNumber shift(0); BigNumber step(1); vector<bitset<kMaxN> > can, can_power; vector<bitset<kMaxN> > Multiply(const vector<bitset<kMaxN> >& a, const vector<bitset<kMaxN> >& b) { vector<bitset<kMaxN> > ret(n); for (int i = 0; i < n; ++i) for (int j = 0; j < n; ++j) if (a[i].test(j)) ret[i] |= b[j]; return ret; } vector<bitset<kMaxN> > Power(const vector<bitset<kMaxN> >& b, BigNumber exp) { /* cerr << "Computing power "; exp.Print(); */ if (exp == 1) return b; vector<bitset<kMaxN> > half = Power(b, exp / 2); vector<bitset<kMaxN> > full = Multiply(half, half); if (exp % 2) return Multiply(full, b); else return full; } void CheckAndAdvance() { if ((robots & bad).none()) { shift.Printf(); exit(0); } /* cerr << "Advancing "; step.Print(); cerr << "Power is "; power.Print(); */ if (power != step) { can_power = Power(can, step); power = step; } bitset<kMaxN> robots_new; // cerr << "can_power size " << can_power.size() << endl; for (int j = 0; j < n; ++j) if (robots.test(j)) robots_new |= can_power[j]; robots = robots_new; // cerr << "Increasing shift." << endl; shift += step; /* cerr << "New shift " << flush; shift.Print(); */ } long long Gcd(long long a, long long b) { // cerr << "Gcd " << a << ' ' << b << endl; while (true) { if (!a) return b; b %= a; if (!b) return a; a %= b; } } long long Gcd(const BigNumber& a, const long long b) { assert(b != 0); return Gcd(a % b, b); } BigNumber Lcm(const BigNumber& a, const long long b) { return a * (b / Gcd(a, b)); } long long Lcm(const long long a, const long long b) { return a * (b / Gcd(a, b)); } int main() { int b; int r; scanf("%d%d%d", &n, &b, &r); can.resize(n); for (int i = 0; i < n; ++i) for (int j = 0; j < n; ++j) { char c; do { scanf("%c", &c); } while (c != '0' && c != '1'); if (c == '1') can[i].set(j); } power = 1; can_power = can; for (int i = 0; i < r; ++i) { int robot; scanf("%d", &robot); robots.set(robot - 1); } for (int i = b; i < n; ++i) bad.set(i); /* const int brute_limit = kBrute / n; for (int i = 0; i < brute_limit; ++i) { } printf("-1\n"); */ vector<vector<pair<int, int> > > dist(n, vector<pair<int, int> >(n, make_pair(kInfinity, kInfinity))); for (int i = 0; i < n; ++i) for (int j = 0; j < n; ++j) if (can[i][j]) dist[i][j] = make_pair(1, kInfinity); { bool change = true; while (change) { change = false; for (int i = 0; i < n; ++i) for (int j = 0; j < n; ++j) for (int k = 0; k < n; ++k) { pair<int, int> better = make_pair(dist[j][i].first + dist[i][k].first, min(dist[j][i].second, dist[i][k].second)); if (j == i && dist[j][i].first < kInfinity) better = min(better, make_pair(dist[i][k].first, dist[j][i].first)); if (i == k && dist[i][k].first < kInfinity) better = min(better, make_pair(dist[j][i].first, dist[i][k].first)); if (better < dist[j][k]) { dist[j][k] = better; change = true; } } } } /* for (int i = 0; i < n; ++i) { for (int j = 0; j < n; ++j) { if (dist[i][j].first == kInfinity) cerr << "- "; else cerr << dist[i][j].first << ',' << dist[i][j].second << ' '; } cerr << endl; } */ vector<vector<bool> > avoid(n + 1); for (int i = 1; i <= n; ++i) avoid[i].resize(i); for (int i = n - 1; i >= b; --i) { int max_reach = robots.test(i) ? 0 : kInfinity; for (int j = 0; j < n; ++j) if (robots.test(j)) if (dist[j][i].first < kInfinity) if (max_reach == kInfinity || dist[j][i].first > max_reach) max_reach = dist[j][i].first; // If max_reach == kInfinity, we can simply forget about this guy. if (max_reach < kInfinity) { // cerr << "Max reach: " << max_reach << endl; // Just store the congruences (slighly bluffy here). for (int j = 0; j < n; ++j) if (robots.test(j)) { const int distance = dist[j][i].first; if (distance < kInfinity) { const int period = dist[j][i].second; if (period < kInfinity) { avoid[period][(shift + distance) % period] = true; // cerr << i << ": avoid " << period << ' ' << (shift + distance) % period << endl; } } } // We can simply forward time and then forget about this guy. while (max_reach-- >= 0) CheckAndAdvance(); } } // Now we just need to satisfy the congruences. { bool change = true; while (change) { change = false; for (int i = 1; i <= n; ++i) for (int j = 0; j < i; ++j) for (int k = i; k <= n; k += i) { bool all_avoid = true; for (int l = j; l < k; l += i) all_avoid &= avoid[k][l]; if (avoid[i][j] != all_avoid) { change = true; if (all_avoid) avoid[i][j] = true; else for (int l = j; l < k; l += i) avoid[k][l] = true; } } } } for (int i = 1; i <= n; ++i) { bool contradiction = true; for (int j = 0; j < i; ++j) { // if (avoid[i][j]) cerr << "Avoid " << i << ' ' << j << endl; contradiction &= avoid[i][j]; } if (contradiction) { printf("-1\n"); return 0; } } step = 1; vector<int> choice(n + 1, -1); for (int i = n; i >= 1; --i) { // cerr << "Checking modulo " << i << endl; if (choice[i] != -1) { if (shift % i != choice[i]) { cerr << "Choice mismatch." << endl; printf("-1\n"); return 0; } } else { bool freedom = true; for (int j = 0; j < i; ++j) if (avoid[i][j]) freedom = false; if (!freedom) { for (int j = 0; j < i; ++j) if (avoid[i][shift % i]) CheckAndAdvance(); else break; if (avoid[i][shift % i]) { cerr << "This should have been detected earlier." << endl; printf("-1\n"); return 0; } /* shift.Print(); cerr << "Remainder by " << i << " is " << shift % i << endl; */ for (int j = 1; j <= i; ++j) if (i % j == 0) choice[j] = shift % j; /* cerr << "Old step "; step.Print(); cerr << "Computing LCM with " << i << endl; */ step = Lcm(step, i); /* cerr << "New step "; step.Print(); */ } } } CheckAndAdvance(); cerr << "This shouldn't be happenning, really." << endl; printf("-1\n"); // shift.Printf(); return 0; } |