#include <climits> #include <cstdio> #include <cstdlib> #include <cstring> #include <string> #include <vector> using namespace std; inline int clp2(int x) { x = x - 1; x |= (x >> 1); x |= (x >> 2); x |= (x >> 4); x |= (x >> 8); x |= (x >> 16); return (x + 1); } struct Node { Node *left_; Node *right_; int x_, y_; int w_, W_; Node(int x, int y) { y = x + clp2(y - x + 1) - 1; x_ = x; y_ = y; w_ = W_ = 0; if (x != y) { left_ = new Node(x, (x + y - 1) / 2); right_ = new Node((x + y + 1) / 2, y); } else { left_ = nullptr; right_ = nullptr; } } ~Node() { if (left_ != nullptr) { delete left_; } if (right_ != nullptr) { delete right_; } } void Insert(int x, int y, int v) { x = max(x, x_); y = min(y, y_); if ((x_ == x) && (y_ == y)) { w_ += v; return; } if ((left_ != nullptr) && (left_->y_ >= x)) { left_->Insert(x, y, v); } if ((right_ != nullptr) && (right_->x_ <= y)) { right_->Insert(x, y, v); } W_ = min(left_->W_ + left_->w_, right_->W_ + right_->w_); } int Query(int x, int y) { x = max(x, x_); y = min(y, y_); if ((x_ == x) && (y_ == y)) { return (W_ + w_); } int m = INT_MAX; if ((left_ != nullptr) && (left_->y_ >= x)) { m = min(m, left_->Query(x, y)); } if ((right_ != nullptr) && (right_->x_ <= y)) { m = min(m, right_->Query(x, y)); } return (m + w_); } int QueryIndex(int x, int y, int v) { x = max(x, x_); y = min(y, y_); if (Query(x_, y_) > v) { return -1; } else if (x_ == y_) { return x; } int m = -1; if ((left_ != nullptr) && (left_->y_ >= x)) { m = left_->QueryIndex(x, y, v - w_); } if ((m == -1) && (right_ != nullptr) && (right_->x_ <= y)) { m = right_->QueryIndex(x, y, v - w_); } return m; } }; struct player { int idx; // Player index. int cash; // Initial cash. int cash_left; // How much cash is left after playing the maximum number of rounds without // going bankrupt. int rounds; // Number of whole cycles the player will be in game. }; player pl[1000000 + 2]; struct item { item(int idx_) : idx(idx_), min_value(0) { } int idx; // Index in the global period. int min_value; // The minimum value in the cycle, starting at this item. vector<player *> players; // Pointers to descriptors of players which start at this offset. }; struct cycle { cycle(int sum_) : sum(sum_) { } int sum; vector<item> items; }; char period[1000000 + 2]; bool visited[1000000 + 2]; vector<int> buckets[1000000 + 2]; vector<cycle> cycles; int main() { int n; scanf("%d", &n); for (int i = 0; i < n; i++) { pl[i].idx = i; scanf("%d", &pl[i].cash); } int m; scanf("%d", &m); scanf("%s", period); for (int i = 0; i < n; i++) { buckets[i % m].push_back(i); } long long wyn = LLONG_MAX; memset(visited, false, sizeof(visited)); // For each cycle... for (int i = 0; i < m; i++) { if (visited[i]) { continue; } cycles.emplace_back(0); auto& cycle = cycles.back(); // Calculate the overall cycle. int v = i; while (!visited[v]) { cycle.items.emplace_back(v); auto &it = cycle.items.back(); // Calculate all players corresponding to this item. for (int j = 0; j < buckets[v].size(); j++) { it.players.push_back(&pl[buckets[v][j]]); } if (period[v] == 'W') { cycle.sum++; } else { cycle.sum--; } visited[v] = true; v = ((v + (n % m)) % m); } // Calculate minimum values in the cycle for each offset. int partial_sum = 0; Node *tree = new Node(0, cycle.items.size() - 1); for (int j = 0; j < cycle.items.size(); j++) { if (period[cycle.items[j].idx] == 'W') { partial_sum++; } else { partial_sum--; } tree->Insert(j, j, partial_sum); } for (int j = 0; j < cycle.items.size(); j++) { cycle.items[j].min_value = tree->Query(0, cycle.items.size() - 1); // Calculate the number of full rounds for each player starting at this offset. for (player *pp : cycle.items[j].players) { if (pp->cash + cycle.items[j].min_value <= 0) { // Not enough cash for even a single round. pp->rounds = 0; pp->cash_left = pp->cash; } else if (cycle.sum >= 0) { // We can survive a full round and the overall sum is non-negative, // so we'll never run out of money. pp->rounds = -1; pp->cash_left = -1; } else { // rounds = ceil((cash - min_value) / sum) pp->rounds = (pp->cash + cycle.items[j].min_value + ((-cycle.sum) - 1)) / (-cycle.sum); pp->cash_left = pp->cash + (pp->rounds * cycle.sum); } if (pp->rounds != -1) { int turns = tree->QueryIndex(j, cycle.items.size() - 1, -pp->cash_left); if (turns != -1) { turns -= j; } else if (j > 0) { turns = tree->QueryIndex(0, j - 1, -pp->cash_left); if (turns != -1) { turns += ((cycle.items.size() - 1) - j + 1); } } // Make absolutely sure that all parts of the expression are casted to long long. :-) wyn = min(wyn, (long long)pp->idx + ((long long)pp->rounds * (long long)n * (long long)cycle.items.size()) + ((long long)turns * (long long)n) + 1LL); } } int value; if (period[cycle.items[j].idx] == 'W') { value = 1; } else { value = -1; } if (j != cycle.items.size() - 1) { int prev_idx; if (j == 0) { prev_idx = cycle.items.size() - 1; } else { prev_idx = j - 1; } tree->Insert(j + 1, cycle.items.size() - 1, -value); if (j > 0) { tree->Insert(0, j - 1, -value); } tree->Insert(j, j, (tree->Query(prev_idx, prev_idx) + value) - tree->Query(j, j)); } } delete tree; } if (wyn == LLONG_MAX) { printf("-1\n"); } else { printf("%lld\n", wyn); } 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 | #include <climits> #include <cstdio> #include <cstdlib> #include <cstring> #include <string> #include <vector> using namespace std; inline int clp2(int x) { x = x - 1; x |= (x >> 1); x |= (x >> 2); x |= (x >> 4); x |= (x >> 8); x |= (x >> 16); return (x + 1); } struct Node { Node *left_; Node *right_; int x_, y_; int w_, W_; Node(int x, int y) { y = x + clp2(y - x + 1) - 1; x_ = x; y_ = y; w_ = W_ = 0; if (x != y) { left_ = new Node(x, (x + y - 1) / 2); right_ = new Node((x + y + 1) / 2, y); } else { left_ = nullptr; right_ = nullptr; } } ~Node() { if (left_ != nullptr) { delete left_; } if (right_ != nullptr) { delete right_; } } void Insert(int x, int y, int v) { x = max(x, x_); y = min(y, y_); if ((x_ == x) && (y_ == y)) { w_ += v; return; } if ((left_ != nullptr) && (left_->y_ >= x)) { left_->Insert(x, y, v); } if ((right_ != nullptr) && (right_->x_ <= y)) { right_->Insert(x, y, v); } W_ = min(left_->W_ + left_->w_, right_->W_ + right_->w_); } int Query(int x, int y) { x = max(x, x_); y = min(y, y_); if ((x_ == x) && (y_ == y)) { return (W_ + w_); } int m = INT_MAX; if ((left_ != nullptr) && (left_->y_ >= x)) { m = min(m, left_->Query(x, y)); } if ((right_ != nullptr) && (right_->x_ <= y)) { m = min(m, right_->Query(x, y)); } return (m + w_); } int QueryIndex(int x, int y, int v) { x = max(x, x_); y = min(y, y_); if (Query(x_, y_) > v) { return -1; } else if (x_ == y_) { return x; } int m = -1; if ((left_ != nullptr) && (left_->y_ >= x)) { m = left_->QueryIndex(x, y, v - w_); } if ((m == -1) && (right_ != nullptr) && (right_->x_ <= y)) { m = right_->QueryIndex(x, y, v - w_); } return m; } }; struct player { int idx; // Player index. int cash; // Initial cash. int cash_left; // How much cash is left after playing the maximum number of rounds without // going bankrupt. int rounds; // Number of whole cycles the player will be in game. }; player pl[1000000 + 2]; struct item { item(int idx_) : idx(idx_), min_value(0) { } int idx; // Index in the global period. int min_value; // The minimum value in the cycle, starting at this item. vector<player *> players; // Pointers to descriptors of players which start at this offset. }; struct cycle { cycle(int sum_) : sum(sum_) { } int sum; vector<item> items; }; char period[1000000 + 2]; bool visited[1000000 + 2]; vector<int> buckets[1000000 + 2]; vector<cycle> cycles; int main() { int n; scanf("%d", &n); for (int i = 0; i < n; i++) { pl[i].idx = i; scanf("%d", &pl[i].cash); } int m; scanf("%d", &m); scanf("%s", period); for (int i = 0; i < n; i++) { buckets[i % m].push_back(i); } long long wyn = LLONG_MAX; memset(visited, false, sizeof(visited)); // For each cycle... for (int i = 0; i < m; i++) { if (visited[i]) { continue; } cycles.emplace_back(0); auto& cycle = cycles.back(); // Calculate the overall cycle. int v = i; while (!visited[v]) { cycle.items.emplace_back(v); auto &it = cycle.items.back(); // Calculate all players corresponding to this item. for (int j = 0; j < buckets[v].size(); j++) { it.players.push_back(&pl[buckets[v][j]]); } if (period[v] == 'W') { cycle.sum++; } else { cycle.sum--; } visited[v] = true; v = ((v + (n % m)) % m); } // Calculate minimum values in the cycle for each offset. int partial_sum = 0; Node *tree = new Node(0, cycle.items.size() - 1); for (int j = 0; j < cycle.items.size(); j++) { if (period[cycle.items[j].idx] == 'W') { partial_sum++; } else { partial_sum--; } tree->Insert(j, j, partial_sum); } for (int j = 0; j < cycle.items.size(); j++) { cycle.items[j].min_value = tree->Query(0, cycle.items.size() - 1); // Calculate the number of full rounds for each player starting at this offset. for (player *pp : cycle.items[j].players) { if (pp->cash + cycle.items[j].min_value <= 0) { // Not enough cash for even a single round. pp->rounds = 0; pp->cash_left = pp->cash; } else if (cycle.sum >= 0) { // We can survive a full round and the overall sum is non-negative, // so we'll never run out of money. pp->rounds = -1; pp->cash_left = -1; } else { // rounds = ceil((cash - min_value) / sum) pp->rounds = (pp->cash + cycle.items[j].min_value + ((-cycle.sum) - 1)) / (-cycle.sum); pp->cash_left = pp->cash + (pp->rounds * cycle.sum); } if (pp->rounds != -1) { int turns = tree->QueryIndex(j, cycle.items.size() - 1, -pp->cash_left); if (turns != -1) { turns -= j; } else if (j > 0) { turns = tree->QueryIndex(0, j - 1, -pp->cash_left); if (turns != -1) { turns += ((cycle.items.size() - 1) - j + 1); } } // Make absolutely sure that all parts of the expression are casted to long long. :-) wyn = min(wyn, (long long)pp->idx + ((long long)pp->rounds * (long long)n * (long long)cycle.items.size()) + ((long long)turns * (long long)n) + 1LL); } } int value; if (period[cycle.items[j].idx] == 'W') { value = 1; } else { value = -1; } if (j != cycle.items.size() - 1) { int prev_idx; if (j == 0) { prev_idx = cycle.items.size() - 1; } else { prev_idx = j - 1; } tree->Insert(j + 1, cycle.items.size() - 1, -value); if (j > 0) { tree->Insert(0, j - 1, -value); } tree->Insert(j, j, (tree->Query(prev_idx, prev_idx) + value) - tree->Query(j, j)); } } delete tree; } if (wyn == LLONG_MAX) { printf("-1\n"); } else { printf("%lld\n", wyn); } return 0; } |