#include <cstdio> #include <algorithm> using namespace std; const int maxN = 1000000, maxTreeSize = (1 << 22), INFint = 1000000000; const long long INFLL = 1000000000000000000LL; struct UglyTree { private: int offset, query_begin, query_end, sum[maxTreeSize], min_on_segment[maxTreeSize], max_on_segment[maxTreeSize]; int target, proper_base_vertex; int current_pref, res; bool found; void check_base_vertices(int v, int left, int right) { if (found or (query_begin >= right) or (query_end <= left)) return; if ((query_begin <= left) and (query_end >= right)) { if ((min_on_segment[v] <= target) and (max_on_segment[v] >= target)) { proper_base_vertex = v; found = 1; } else target -= sum[v]; return; } check_base_vertices(v * 2, left, (left + right) / 2); check_base_vertices(v*2+1, (left + right) / 2, right); } void look_min_pref(int v, int left, int right) { if ((query_begin >= right) or (query_end <= left)) return; if ((query_begin <= left) and (query_end >= right)) { res = min(res, current_pref + min_on_segment[v]); current_pref += sum[v]; return; } look_min_pref(v * 2, left, (left + right) / 2); look_min_pref(v*2+1, (left + right) / 2, right); } public: void reinitialize(int n, int* T) { offset = 1; while (offset < n) offset *= 2; for (int i = offset; i < offset + n; i++) sum[i] = min_on_segment[i] = max_on_segment[i] = T[i - offset]; for (int i = offset + n; i < offset * 2; i++) { sum[i] = 0; min_on_segment[i] = INFint; max_on_segment[i] = -INFint; } for (int i=offset-1; i>0; i--) { sum[i] = sum[i * 2] + sum[i*2+1]; min_on_segment[i] = min(min_on_segment[i * 2], sum[i * 2] + min_on_segment[i*2+1]); max_on_segment[i] = max(max_on_segment[i * 2], sum[i * 2] + max_on_segment[i*2+1]); } } int first_index_with_such_sum(int begin, int end, int wanted_sum) { query_begin = begin + offset; query_end = end + offset; target = wanted_sum; found = 0; check_base_vertices(1, offset, offset * 2); int v = proper_base_vertex; while (v < offset) { if ((min_on_segment[v * 2] <= target) and (max_on_segment[v * 2] >= target)) v *= 2; else { target -= sum[v * 2]; v = v * 2 + 1; } } return (v + 1 - offset); } int min_of_prefs(int begin, int end) { query_begin = begin + offset; query_end = end + offset; current_pref = 0; res = INFint; look_min_pref(1, offset, offset * 2); return res; } }; int in[maxN], T[maxN], indexes[maxN * 2], values[maxN * 2], min_pref[maxN]; bool vis[maxN]; long long res[maxN]; UglyTree tree; int main() { int n; scanf ("%d", &n); for (int i=0; i<n; i++) scanf ("%d", &in[i]); int m; scanf ("%d", &m); char W[maxN + 1]; scanf ("%s", W); for (int i=0; i<m; i++) T[i] = (W[i] == 'W') ? 1 : -1; for (int i=0; i<m; i++) { if (vis[i]) continue; int cycle_length = 0, cycle_sum = 0; int v = i; while (!vis[v]) { cycle_sum += T[v]; indexes[cycle_length] = v; values[cycle_length++] = T[v]; vis[v] = 1; v = (v + n) % m; } for (int j = cycle_length; j < cycle_length * 2; j++) values[j] = values[j - cycle_length]; tree.reinitialize(cycle_length * 2, values); for (int j=0; j<cycle_length; j++) min_pref[j] = tree.min_of_prefs(j, j + cycle_length); for (int k=0; k<cycle_length; k++) { for (int j=indexes[k]; j<n; j+=m) { if (cycle_sum >= 0) { if (in[j] + min_pref[k] > 0) res[j] = INFLL; else res[j] = tree.first_index_with_such_sum(k, k + cycle_length, -in[j]) - k; continue; } int tail = cycle_sum - min_pref[k]; int amount_of_cycles = max(0, (in[j] - 1 - tail) / -cycle_sum); in[j] += amount_of_cycles * cycle_sum; res[j] = (long long)amount_of_cycles * cycle_length + tree.first_index_with_such_sum(k, k + cycle_length, -in[j]) - k; //printf("amount: %d, tail: %d, res: %lld\n", amount_of_cycles, tail, res[j]); } } } long long result = INFLL; for (int i=0; i<n; i++) { if (res[i] == INFLL) continue; result = min(result, (long long)(res[i] - 1) * n + i + 1); } printf("%lld\n", (result == INFLL) ? -1LL : result); 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 | #include <cstdio> #include <algorithm> using namespace std; const int maxN = 1000000, maxTreeSize = (1 << 22), INFint = 1000000000; const long long INFLL = 1000000000000000000LL; struct UglyTree { private: int offset, query_begin, query_end, sum[maxTreeSize], min_on_segment[maxTreeSize], max_on_segment[maxTreeSize]; int target, proper_base_vertex; int current_pref, res; bool found; void check_base_vertices(int v, int left, int right) { if (found or (query_begin >= right) or (query_end <= left)) return; if ((query_begin <= left) and (query_end >= right)) { if ((min_on_segment[v] <= target) and (max_on_segment[v] >= target)) { proper_base_vertex = v; found = 1; } else target -= sum[v]; return; } check_base_vertices(v * 2, left, (left + right) / 2); check_base_vertices(v*2+1, (left + right) / 2, right); } void look_min_pref(int v, int left, int right) { if ((query_begin >= right) or (query_end <= left)) return; if ((query_begin <= left) and (query_end >= right)) { res = min(res, current_pref + min_on_segment[v]); current_pref += sum[v]; return; } look_min_pref(v * 2, left, (left + right) / 2); look_min_pref(v*2+1, (left + right) / 2, right); } public: void reinitialize(int n, int* T) { offset = 1; while (offset < n) offset *= 2; for (int i = offset; i < offset + n; i++) sum[i] = min_on_segment[i] = max_on_segment[i] = T[i - offset]; for (int i = offset + n; i < offset * 2; i++) { sum[i] = 0; min_on_segment[i] = INFint; max_on_segment[i] = -INFint; } for (int i=offset-1; i>0; i--) { sum[i] = sum[i * 2] + sum[i*2+1]; min_on_segment[i] = min(min_on_segment[i * 2], sum[i * 2] + min_on_segment[i*2+1]); max_on_segment[i] = max(max_on_segment[i * 2], sum[i * 2] + max_on_segment[i*2+1]); } } int first_index_with_such_sum(int begin, int end, int wanted_sum) { query_begin = begin + offset; query_end = end + offset; target = wanted_sum; found = 0; check_base_vertices(1, offset, offset * 2); int v = proper_base_vertex; while (v < offset) { if ((min_on_segment[v * 2] <= target) and (max_on_segment[v * 2] >= target)) v *= 2; else { target -= sum[v * 2]; v = v * 2 + 1; } } return (v + 1 - offset); } int min_of_prefs(int begin, int end) { query_begin = begin + offset; query_end = end + offset; current_pref = 0; res = INFint; look_min_pref(1, offset, offset * 2); return res; } }; int in[maxN], T[maxN], indexes[maxN * 2], values[maxN * 2], min_pref[maxN]; bool vis[maxN]; long long res[maxN]; UglyTree tree; int main() { int n; scanf ("%d", &n); for (int i=0; i<n; i++) scanf ("%d", &in[i]); int m; scanf ("%d", &m); char W[maxN + 1]; scanf ("%s", W); for (int i=0; i<m; i++) T[i] = (W[i] == 'W') ? 1 : -1; for (int i=0; i<m; i++) { if (vis[i]) continue; int cycle_length = 0, cycle_sum = 0; int v = i; while (!vis[v]) { cycle_sum += T[v]; indexes[cycle_length] = v; values[cycle_length++] = T[v]; vis[v] = 1; v = (v + n) % m; } for (int j = cycle_length; j < cycle_length * 2; j++) values[j] = values[j - cycle_length]; tree.reinitialize(cycle_length * 2, values); for (int j=0; j<cycle_length; j++) min_pref[j] = tree.min_of_prefs(j, j + cycle_length); for (int k=0; k<cycle_length; k++) { for (int j=indexes[k]; j<n; j+=m) { if (cycle_sum >= 0) { if (in[j] + min_pref[k] > 0) res[j] = INFLL; else res[j] = tree.first_index_with_such_sum(k, k + cycle_length, -in[j]) - k; continue; } int tail = cycle_sum - min_pref[k]; int amount_of_cycles = max(0, (in[j] - 1 - tail) / -cycle_sum); in[j] += amount_of_cycles * cycle_sum; res[j] = (long long)amount_of_cycles * cycle_length + tree.first_index_with_such_sum(k, k + cycle_length, -in[j]) - k; //printf("amount: %d, tail: %d, res: %lld\n", amount_of_cycles, tail, res[j]); } } } long long result = INFLL; for (int i=0; i<n; i++) { if (res[i] == INFLL) continue; result = min(result, (long long)(res[i] - 1) * n + i + 1); } printf("%lld\n", (result == INFLL) ? -1LL : result); return 0; } |