#include <iostream> #include <vector> #include <algorithm> #include <string> #define FOR(i,b,e) for(int i=(b); i <= (e); ++i) #define FORD(i,b,e) for(int i=(b); i >= (e); --i) #define SIZE(c) (int) (c).size() #define FORE(i,c) FOR(i,0,SIZE(c)-1) #define PB push_back #define MP make_pair #define ST first #define ND second using namespace std; typedef long long int LLI; typedef pair < int , int > PII; typedef vector < int > VI; typedef vector < PII > VP; typedef vector < VP > VVP; const int SMALL_INF = 1000000001; const LLI INF = 1000000000000000001LL; /*************************************************************************/ struct MinStack { VI S; VI M; void Push(int x) { S.PB(x); if (M.empty()) M.PB(x); else M.PB( min(x, M.back()) ); } int Pop() { int b = S.back(); S.pop_back(); M.pop_back(); return b; } int Min() { if (SIZE(M)) return (M.back()); else return SMALL_INF; } bool Empty() { return S.empty(); } }; struct MinQueue { MinStack S1, S2; VI Occurence; int offset; int minVal, maxVal; MinQueue(int minVal, int maxVal) { this->minVal = minVal; this->maxVal = maxVal; offset = -minVal; Occurence.resize(maxVal - minVal + 1, -1); } void Push(int x, int index) { S2.Push(x); Occurence[x + offset] = index; } int Pop() { if (S1.Empty()) while (!S2.Empty()) S1.Push(S2.Pop()); return S1.Pop(); } int Min() { return min(S1.Min(), S2.Min()); } int FirstOccurence(int val) { if (val < minVal || val > maxVal) return -1; else return Occurence[val + offset]; } }; /*************************************************************************/ LLI solve(LLI step, VI &M, VVP &start) { int m = SIZE(M); FOR(i,0,m-1) M.PB(M[i]); FOR(i,1,2*m-1) M[i] += M[i-1]; LLI sum = M.back() / 2; LLI ans = INF; MinQueue Queue(-2*m, 2*m); FORD(i,2*m-1,m) Queue.Push(M[i], i); FORD(i,m-1,0) { Queue.Pop(); Queue.Push(M[i], i); LLI pref = (i ? M[i-1] : 0); LLI minDrop = Queue.Min() - pref; if (minDrop < 0) for (PII boy : start[i]) { LLI money = boy.ND; LLI here = boy.ST; if (sum < 0) { LLI over = max(0LL, money + minDrop); LLI cycles = (over - sum - 1) / (-sum); money += cycles * sum; here += cycles * m * step; } if (money + minDrop <= 0) { int lookingFor = pref - money; int pos = Queue.FirstOccurence(lookingFor); here += step * (pos - i); ans = min(ans, here); } } } return ans; } /*************************************************************************/ int main() { ios_base::sync_with_stdio(0); LLI n; cin >> n; VI T(n); FORE(i,T) cin >> T[i]; LLI m; cin >> m; string s; cin >> s; LLI gcd = __gcd(n, m); LLI ans = INF; FOR(i,0,gcd-1) { VI M; VVP start; /* M - some particular elements of the machine cycle */ /* start - for each position in M boys that start there */ int j = i; do { start.PB(VP()); for (int boy = j; boy < n; boy += m) start.back().PB( MP(boy, T[boy]) ); M.PB( (s[j] == 'W') ? 1 : -1 ); j = (j + n)%m; } while (j != i); LLI result = solve(n, M, start); ans = min(ans, result); } if (ans == INF) cout << -1; else cout << 1 + ans; 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 | #include <iostream> #include <vector> #include <algorithm> #include <string> #define FOR(i,b,e) for(int i=(b); i <= (e); ++i) #define FORD(i,b,e) for(int i=(b); i >= (e); --i) #define SIZE(c) (int) (c).size() #define FORE(i,c) FOR(i,0,SIZE(c)-1) #define PB push_back #define MP make_pair #define ST first #define ND second using namespace std; typedef long long int LLI; typedef pair < int , int > PII; typedef vector < int > VI; typedef vector < PII > VP; typedef vector < VP > VVP; const int SMALL_INF = 1000000001; const LLI INF = 1000000000000000001LL; /*************************************************************************/ struct MinStack { VI S; VI M; void Push(int x) { S.PB(x); if (M.empty()) M.PB(x); else M.PB( min(x, M.back()) ); } int Pop() { int b = S.back(); S.pop_back(); M.pop_back(); return b; } int Min() { if (SIZE(M)) return (M.back()); else return SMALL_INF; } bool Empty() { return S.empty(); } }; struct MinQueue { MinStack S1, S2; VI Occurence; int offset; int minVal, maxVal; MinQueue(int minVal, int maxVal) { this->minVal = minVal; this->maxVal = maxVal; offset = -minVal; Occurence.resize(maxVal - minVal + 1, -1); } void Push(int x, int index) { S2.Push(x); Occurence[x + offset] = index; } int Pop() { if (S1.Empty()) while (!S2.Empty()) S1.Push(S2.Pop()); return S1.Pop(); } int Min() { return min(S1.Min(), S2.Min()); } int FirstOccurence(int val) { if (val < minVal || val > maxVal) return -1; else return Occurence[val + offset]; } }; /*************************************************************************/ LLI solve(LLI step, VI &M, VVP &start) { int m = SIZE(M); FOR(i,0,m-1) M.PB(M[i]); FOR(i,1,2*m-1) M[i] += M[i-1]; LLI sum = M.back() / 2; LLI ans = INF; MinQueue Queue(-2*m, 2*m); FORD(i,2*m-1,m) Queue.Push(M[i], i); FORD(i,m-1,0) { Queue.Pop(); Queue.Push(M[i], i); LLI pref = (i ? M[i-1] : 0); LLI minDrop = Queue.Min() - pref; if (minDrop < 0) for (PII boy : start[i]) { LLI money = boy.ND; LLI here = boy.ST; if (sum < 0) { LLI over = max(0LL, money + minDrop); LLI cycles = (over - sum - 1) / (-sum); money += cycles * sum; here += cycles * m * step; } if (money + minDrop <= 0) { int lookingFor = pref - money; int pos = Queue.FirstOccurence(lookingFor); here += step * (pos - i); ans = min(ans, here); } } } return ans; } /*************************************************************************/ int main() { ios_base::sync_with_stdio(0); LLI n; cin >> n; VI T(n); FORE(i,T) cin >> T[i]; LLI m; cin >> m; string s; cin >> s; LLI gcd = __gcd(n, m); LLI ans = INF; FOR(i,0,gcd-1) { VI M; VVP start; /* M - some particular elements of the machine cycle */ /* start - for each position in M boys that start there */ int j = i; do { start.PB(VP()); for (int boy = j; boy < n; boy += m) start.back().PB( MP(boy, T[boy]) ); M.PB( (s[j] == 'W') ? 1 : -1 ); j = (j + n)%m; } while (j != i); LLI result = solve(n, M, start); ans = min(ans, result); } if (ans == INF) cout << -1; else cout << 1 + ans; return 0; } /*************************************************************************/ |