#include <cstdlib> #include <iostream> #include <string> using namespace std; const int INFINITY = 1000000000; const long long LINFINITY = INFINITY; int cash[1000000]; int cycle[1000000]; int Pcash[1000000]; int Pcycle[1000000]; int RcycleMap[1000000]; // maps from index in reverse cycle to normal index int PcycleMap[1000000]; // maps from normal index to rcycle index int Rcycle[1000000]; int RcycleMin[1000000]; long long Diff[1000000]; long long Shift[1000000]; int minEpoch[1000000]; int NWD(int a, int b) { if(b!=0) return NWD(b,a%b); return a; } int FingBestFromCurrent(int n, int m, int im) { int best = RcycleMap[im]; int Value = Pcash[best]; for(int i = RcycleMap[im]; i < n; i += m) { if(Pcash[i] < Value) { best = i; Value = Pcash[i]; } } return best; } long long Process(int n, int m) { //rewerse cycle for single player int change = 0; int minvalue = 0; int minimalEpoch = INFINITY; for(int i = 0, s = 0; i < m; i++) { RcycleMap[i] = s; PcycleMap[s] = i; Rcycle[i] = Pcycle[s]; change += Rcycle[i]; if(change < minvalue) minvalue = change; s = (s + n) % m; } //calculate min for different starting round for(int i = 0; i < m; i++) { RcycleMin[i] = minvalue; minvalue += Rcycle[i]; if(minvalue > change) minvalue = change; } for(int i = 0; i < n && i < m; i++) { int val = Pcash[i]; int idx = i; for(int j = i + m; j < n; j+= m) { if(Pcash[j] < val) { minEpoch[idx] = INFINITY; val = Pcash[j]; idx = j; } else { minEpoch[j] = INFINITY; } } int Ri = PcycleMap[idx % m]; int min = RcycleMin[Ri]; if(val + min < 0) minimalEpoch = 0; else { int mE = (val + min) / (-change) + 1; if(val + change * mE == 0) mE--; if(change >= 0 && mE != 0) mE = INFINITY; minEpoch[idx] = mE; if(mE < minimalEpoch) minimalEpoch = mE; } } if(minimalEpoch == INFINITY) { return -1; } long long minResult = LINFINITY * LINFINITY; for(int i = 0; i < n; i++) { if(minEpoch[i] != minimalEpoch) continue; int cash = Pcash[i] + change * minimalEpoch; int Ri = PcycleMap[i % m]; bool bFound = false; for(int j = 0; j < m; j++) { cash += Rcycle[Ri]; if(cash == 0) { long long result = minimalEpoch * n * m + j * n + i; if(result < minResult) minResult = result; bFound = true; break; } Ri = (Ri + 1) % m; } // if(bFound == false) // cout<<"something wrong, i = "<<i<<endl; } if(minResult == LINFINITY * LINFINITY) return -1; else return minResult; /* //we are sure that if solution exist than we can find them i single cycle int currentValue = Pcash[0]; long long currentDiff = 0; long long currentShift = 0; for(int im = 0; im < m; im++) { int globalShift = im * n; //we need to find best element which start procees from current cycle element int in = FingBestFromCurrent(n, m, im); Diff[im] = ; Shift[im] = in; if(Pcash[in] <= currentValue) { } }*/ } int main(int argc, char *argv[]) { ios_base::sync_with_stdio(0); int n, m; cin >> n; for(int i = 0; i < n; i++) { cin >> cash[i]; } cin >> m; string c; cin >> c; for(int i = 0; i < m; i++) { if(c[i] == 'W') cycle[i] = 1; else cycle[i] = -1; } int nwd = NWD(n,m); int Pn = n / nwd; int Pm = m / nwd; long long min = -1; for(int i = 0; i < nwd; i++) { for(int j = 0; j < Pn; j++) { Pcash[j] = cash[j * nwd + i]; } for(int j = 0; j < Pm; j++) { Pcycle[j] = cycle[j * nwd + i]; } long long result = Process(n, m); result = result * nwd + i; if(result != -1 && (result < min || min == -1)) min = result; } if(min == -1) cout<<-1; else cout<<min + 1; }
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 | #include <cstdlib> #include <iostream> #include <string> using namespace std; const int INFINITY = 1000000000; const long long LINFINITY = INFINITY; int cash[1000000]; int cycle[1000000]; int Pcash[1000000]; int Pcycle[1000000]; int RcycleMap[1000000]; // maps from index in reverse cycle to normal index int PcycleMap[1000000]; // maps from normal index to rcycle index int Rcycle[1000000]; int RcycleMin[1000000]; long long Diff[1000000]; long long Shift[1000000]; int minEpoch[1000000]; int NWD(int a, int b) { if(b!=0) return NWD(b,a%b); return a; } int FingBestFromCurrent(int n, int m, int im) { int best = RcycleMap[im]; int Value = Pcash[best]; for(int i = RcycleMap[im]; i < n; i += m) { if(Pcash[i] < Value) { best = i; Value = Pcash[i]; } } return best; } long long Process(int n, int m) { //rewerse cycle for single player int change = 0; int minvalue = 0; int minimalEpoch = INFINITY; for(int i = 0, s = 0; i < m; i++) { RcycleMap[i] = s; PcycleMap[s] = i; Rcycle[i] = Pcycle[s]; change += Rcycle[i]; if(change < minvalue) minvalue = change; s = (s + n) % m; } //calculate min for different starting round for(int i = 0; i < m; i++) { RcycleMin[i] = minvalue; minvalue += Rcycle[i]; if(minvalue > change) minvalue = change; } for(int i = 0; i < n && i < m; i++) { int val = Pcash[i]; int idx = i; for(int j = i + m; j < n; j+= m) { if(Pcash[j] < val) { minEpoch[idx] = INFINITY; val = Pcash[j]; idx = j; } else { minEpoch[j] = INFINITY; } } int Ri = PcycleMap[idx % m]; int min = RcycleMin[Ri]; if(val + min < 0) minimalEpoch = 0; else { int mE = (val + min) / (-change) + 1; if(val + change * mE == 0) mE--; if(change >= 0 && mE != 0) mE = INFINITY; minEpoch[idx] = mE; if(mE < minimalEpoch) minimalEpoch = mE; } } if(minimalEpoch == INFINITY) { return -1; } long long minResult = LINFINITY * LINFINITY; for(int i = 0; i < n; i++) { if(minEpoch[i] != minimalEpoch) continue; int cash = Pcash[i] + change * minimalEpoch; int Ri = PcycleMap[i % m]; bool bFound = false; for(int j = 0; j < m; j++) { cash += Rcycle[Ri]; if(cash == 0) { long long result = minimalEpoch * n * m + j * n + i; if(result < minResult) minResult = result; bFound = true; break; } Ri = (Ri + 1) % m; } // if(bFound == false) // cout<<"something wrong, i = "<<i<<endl; } if(minResult == LINFINITY * LINFINITY) return -1; else return minResult; /* //we are sure that if solution exist than we can find them i single cycle int currentValue = Pcash[0]; long long currentDiff = 0; long long currentShift = 0; for(int im = 0; im < m; im++) { int globalShift = im * n; //we need to find best element which start procees from current cycle element int in = FingBestFromCurrent(n, m, im); Diff[im] = ; Shift[im] = in; if(Pcash[in] <= currentValue) { } }*/ } int main(int argc, char *argv[]) { ios_base::sync_with_stdio(0); int n, m; cin >> n; for(int i = 0; i < n; i++) { cin >> cash[i]; } cin >> m; string c; cin >> c; for(int i = 0; i < m; i++) { if(c[i] == 'W') cycle[i] = 1; else cycle[i] = -1; } int nwd = NWD(n,m); int Pn = n / nwd; int Pm = m / nwd; long long min = -1; for(int i = 0; i < nwd; i++) { for(int j = 0; j < Pn; j++) { Pcash[j] = cash[j * nwd + i]; } for(int j = 0; j < Pm; j++) { Pcycle[j] = cycle[j * nwd + i]; } long long result = Process(n, m); result = result * nwd + i; if(result != -1 && (result < min || min == -1)) min = result; } if(min == -1) cout<<-1; else cout<<min + 1; } |