#include <algorithm> #include <cassert> #include <cstdio> #include <deque> #include <vector> using namespace std; constexpr int MAXN = 1000010; constexpr int MAXM = 1000010; int N; int M; int money[MAXN]; int win_or_loss[MAXM]; // how many rounds x can play (-1 -> inf) long long lasts_rounds[MAXN]; void read_data() { scanf("%d", &N); for (int i = 0; i < N; ++i) { scanf("%d", money + i); lasts_rounds[i] = -2; // dunno } scanf("%d\n", &M); std::vector<char> str(M + 1, 'X'); fgets(str.data(), M, stdin); for (int i = 0; i < M; ++i) { win_or_loss[i] = str[i] == 'W' ? 1 : -1; } // printf("%d\n", N); // for (int i = 0; i < N; ++i) { // printf("%d: %d\n", i, money[i]); // } // printf("%d\n", M); // for (int i = 0; i < M; ++i) { // printf("%d: %d\n", i, win_or_loss[i]); // } } void rot(deque<pair<int, int>>& mins, deque<int>& cycle_indexes, int& vertical_offset, int& horizontal_offset) { // assert(!mins.empty()); int back = cycle_indexes.back(); cycle_indexes.pop_back(); cycle_indexes.push_front(back); ++horizontal_offset; if (win_or_loss[cycle_indexes.front()] == 1) { // printf("moving up slope\n"); ++vertical_offset; // remove above zeros from the beginning while (!mins.empty() && mins.front().first + vertical_offset >= 0) { mins.pop_front(); } // put (0, 0) if the first is up mins.emplace_front(-vertical_offset, -horizontal_offset); } else { // printf("moving down slope\n"); --vertical_offset; // printf("second %d hori_off %d size %d\n", mins.back().second, horizontal_offset, cycle_indexes.size()); if (mins.back().second + horizontal_offset - 1 == cycle_indexes.size()) { // the last down slope becomes shorter ++mins.back().first; --mins.back().second; if (mins.size() >= 2 && mins[mins.size() - 2].first <= mins.back().first) { mins.pop_back(); } } } } int ceill(int a, int b) { return (a + b - 1) / b; } void compute_lasts(int idx, int net_diff, const deque<pair<int, int>>& mins, const deque<int>& cycle_indexes, int vertical_offset, int horizontal_offset) { // printf("comp_lasts %d %d\n", idx, net_diff); // for (int it = 0; it < cycle_indexes.size(); ++it) { // printf("ci %d: %d\n", it, cycle_indexes[it]); // } // for (int it = 0; it < mins.size(); ++it) { // printf("mins %d: %d %d\n", it, mins[it].first + vertical_offset, mins[it].second + horizontal_offset); // } // assert(!mins.empty()); for (int i = idx; i < N; i += M) { int min_of_mins = mins.back().first + vertical_offset; // printf(" lasts %d == ? (mon %d min %d)\n", i, money[i], min_of_mins); if (money[i] > -min_of_mins && net_diff >= 0) { // he'll last foreva lasts_rounds[i] = -1; // printf("foreva\n"); continue; } lasts_rounds[i] = 0; if (net_diff < 0) { // it'll take him r cycles until he has less than or eq -min_of_mins int r = ceill(money[i] + min_of_mins, -net_diff); r = max(0, r); lasts_rounds[i] = (long long) r * (long long) cycle_indexes.size(); money[i] += r * net_diff; // += (<0) } // printf("lasts %lld money %d\n", lasts_rounds[i], money[i]); // find first min which is less (whose abs is less) than current money[i] auto it = lower_bound(mins.begin(), mins.end(), money[i], [vertical_offset](const pair<int, int>& p, int v) { return -(p.first + vertical_offset) < v; }); // printf(" low_bnd %d %d\n", it->first + vertical_offset, it->second + horizontal_offset); lasts_rounds[i] += it->second + horizontal_offset - (-(it->first + vertical_offset) - money[i]); } } void compute_defeat_times(int curr) { // printf("cdt %d\n", curr); // assert(curr < M); deque<int> cycle_indexes; int last = -1; int init_curr = curr; do { cycle_indexes.push_back(curr); curr = (curr + N) % M; } while (curr != init_curr); // fill initial mins (for initial curr) int vertical_offset = 0; int horizontal_offset = 0; // value, position deque<pair<int, int>> mins; int curr_value = 0; mins.emplace_back(0, 0); // curr = init_curr; for (int i = 0; i < cycle_indexes.size(); ++i) { curr_value += win_or_loss[cycle_indexes[i]]; // printf("cv %d %d\n", curr_value, cycle_indexes[i]); if (curr_value == mins.back().first - 1 && i == mins.back().second) { ++mins.back().second; --mins.back().first; } else if (curr_value < mins.back().first) { mins.emplace_back(curr_value, i + 1); } } compute_lasts(cycle_indexes.front(), curr_value,mins, cycle_indexes, vertical_offset, horizontal_offset); for (int i = 1; i < cycle_indexes.size(); ++i) { // rotate graph rot(mins, cycle_indexes, vertical_offset, horizontal_offset); compute_lasts(cycle_indexes.front(), curr_value,mins, cycle_indexes, vertical_offset, horizontal_offset); } } void compute_defeat_times() { for (int i = 0; i < N; ++i) { if (lasts_rounds[i] == -2) { // not computed compute_defeat_times(i); } } // for (int i = 0; i < N; ++i) { // printf("lasts %d -> %lld\n", i, lasts_rounds[i]); // } } long long compute_result() { long long min = -2; long long pos = -2; for (int i = 0; i < N; ++i) { if (lasts_rounds[i] != -1 && (min == -2 || lasts_rounds[i] < min)) { min = lasts_rounds[i]; pos = i; } } if (min == -2) { return -1; } // printf("%lld %d\n", min, pos); return (min - 1) * N + pos + 1; } int main() { read_data(); compute_defeat_times(); printf("%lld\n", compute_result()); }
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 | #include <algorithm> #include <cassert> #include <cstdio> #include <deque> #include <vector> using namespace std; constexpr int MAXN = 1000010; constexpr int MAXM = 1000010; int N; int M; int money[MAXN]; int win_or_loss[MAXM]; // how many rounds x can play (-1 -> inf) long long lasts_rounds[MAXN]; void read_data() { scanf("%d", &N); for (int i = 0; i < N; ++i) { scanf("%d", money + i); lasts_rounds[i] = -2; // dunno } scanf("%d\n", &M); std::vector<char> str(M + 1, 'X'); fgets(str.data(), M, stdin); for (int i = 0; i < M; ++i) { win_or_loss[i] = str[i] == 'W' ? 1 : -1; } // printf("%d\n", N); // for (int i = 0; i < N; ++i) { // printf("%d: %d\n", i, money[i]); // } // printf("%d\n", M); // for (int i = 0; i < M; ++i) { // printf("%d: %d\n", i, win_or_loss[i]); // } } void rot(deque<pair<int, int>>& mins, deque<int>& cycle_indexes, int& vertical_offset, int& horizontal_offset) { // assert(!mins.empty()); int back = cycle_indexes.back(); cycle_indexes.pop_back(); cycle_indexes.push_front(back); ++horizontal_offset; if (win_or_loss[cycle_indexes.front()] == 1) { // printf("moving up slope\n"); ++vertical_offset; // remove above zeros from the beginning while (!mins.empty() && mins.front().first + vertical_offset >= 0) { mins.pop_front(); } // put (0, 0) if the first is up mins.emplace_front(-vertical_offset, -horizontal_offset); } else { // printf("moving down slope\n"); --vertical_offset; // printf("second %d hori_off %d size %d\n", mins.back().second, horizontal_offset, cycle_indexes.size()); if (mins.back().second + horizontal_offset - 1 == cycle_indexes.size()) { // the last down slope becomes shorter ++mins.back().first; --mins.back().second; if (mins.size() >= 2 && mins[mins.size() - 2].first <= mins.back().first) { mins.pop_back(); } } } } int ceill(int a, int b) { return (a + b - 1) / b; } void compute_lasts(int idx, int net_diff, const deque<pair<int, int>>& mins, const deque<int>& cycle_indexes, int vertical_offset, int horizontal_offset) { // printf("comp_lasts %d %d\n", idx, net_diff); // for (int it = 0; it < cycle_indexes.size(); ++it) { // printf("ci %d: %d\n", it, cycle_indexes[it]); // } // for (int it = 0; it < mins.size(); ++it) { // printf("mins %d: %d %d\n", it, mins[it].first + vertical_offset, mins[it].second + horizontal_offset); // } // assert(!mins.empty()); for (int i = idx; i < N; i += M) { int min_of_mins = mins.back().first + vertical_offset; // printf(" lasts %d == ? (mon %d min %d)\n", i, money[i], min_of_mins); if (money[i] > -min_of_mins && net_diff >= 0) { // he'll last foreva lasts_rounds[i] = -1; // printf("foreva\n"); continue; } lasts_rounds[i] = 0; if (net_diff < 0) { // it'll take him r cycles until he has less than or eq -min_of_mins int r = ceill(money[i] + min_of_mins, -net_diff); r = max(0, r); lasts_rounds[i] = (long long) r * (long long) cycle_indexes.size(); money[i] += r * net_diff; // += (<0) } // printf("lasts %lld money %d\n", lasts_rounds[i], money[i]); // find first min which is less (whose abs is less) than current money[i] auto it = lower_bound(mins.begin(), mins.end(), money[i], [vertical_offset](const pair<int, int>& p, int v) { return -(p.first + vertical_offset) < v; }); // printf(" low_bnd %d %d\n", it->first + vertical_offset, it->second + horizontal_offset); lasts_rounds[i] += it->second + horizontal_offset - (-(it->first + vertical_offset) - money[i]); } } void compute_defeat_times(int curr) { // printf("cdt %d\n", curr); // assert(curr < M); deque<int> cycle_indexes; int last = -1; int init_curr = curr; do { cycle_indexes.push_back(curr); curr = (curr + N) % M; } while (curr != init_curr); // fill initial mins (for initial curr) int vertical_offset = 0; int horizontal_offset = 0; // value, position deque<pair<int, int>> mins; int curr_value = 0; mins.emplace_back(0, 0); // curr = init_curr; for (int i = 0; i < cycle_indexes.size(); ++i) { curr_value += win_or_loss[cycle_indexes[i]]; // printf("cv %d %d\n", curr_value, cycle_indexes[i]); if (curr_value == mins.back().first - 1 && i == mins.back().second) { ++mins.back().second; --mins.back().first; } else if (curr_value < mins.back().first) { mins.emplace_back(curr_value, i + 1); } } compute_lasts(cycle_indexes.front(), curr_value,mins, cycle_indexes, vertical_offset, horizontal_offset); for (int i = 1; i < cycle_indexes.size(); ++i) { // rotate graph rot(mins, cycle_indexes, vertical_offset, horizontal_offset); compute_lasts(cycle_indexes.front(), curr_value,mins, cycle_indexes, vertical_offset, horizontal_offset); } } void compute_defeat_times() { for (int i = 0; i < N; ++i) { if (lasts_rounds[i] == -2) { // not computed compute_defeat_times(i); } } // for (int i = 0; i < N; ++i) { // printf("lasts %d -> %lld\n", i, lasts_rounds[i]); // } } long long compute_result() { long long min = -2; long long pos = -2; for (int i = 0; i < N; ++i) { if (lasts_rounds[i] != -1 && (min == -2 || lasts_rounds[i] < min)) { min = lasts_rounds[i]; pos = i; } } if (min == -2) { return -1; } // printf("%lld %d\n", min, pos); return (min - 1) * N + pos + 1; } int main() { read_data(); compute_defeat_times(); printf("%lld\n", compute_result()); } |