import java.io.*; import java.util.*; public class haz { public static void main(String[] args) throws Exception { BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); int boysCount = Integer.parseInt(br.readLine()); int[] boys = new int[boysCount]; String boysString = br.readLine()+' '; int prevIdx = 0; for (int j = 0; j < boysCount; j++) { int idx = boysString.indexOf(' ', prevIdx); boys[j] = Integer.parseInt(boysString.substring(prevIdx, idx)); prevIdx = idx+1; } int cycleLength = Integer.parseInt(br.readLine()); int[] cycle = new int[cycleLength]; for (int j = 0; j < cycle.length; j++) { if (br.read() == 'W') { cycle[j] = 1; } else { cycle[j]= -1; } } int queueLen = (int) (nww(boysCount, cycleLength) / boysCount); int differentCyclesForBoys = cycleLength / queueLen; int[][] queuesForBoys = new int[differentCyclesForBoys][queueLen]; List<Integer>[][] queuesForBoysIdx = new List[differentCyclesForBoys][]; int[][] queuesForBoysAccum = new int[differentCyclesForBoys][cycleLength / differentCyclesForBoys]; int[] offsets = new int[cycleLength]; for (int j = 0; j < differentCyclesForBoys; j++) { for (int k = 0; k < queueLen; k++) { int value = (int) ((j + (long) k * boysCount) % cycleLength); queuesForBoys[j][k] = cycle[value]; offsets[value] = k; } } for (int j = 0; j < differentCyclesForBoys; j++) { int[] queue = queuesForBoys[j]; int[] queueAccu = new int[queue.length]; queueAccu[0] = queue[0]; int maxDrop = 0; for (int k = 1; k < queue.length; k++) { queueAccu[k] = queueAccu[k - 1] + queue[k]; maxDrop = Math.max(maxDrop, -queueAccu[k]); } List<Integer>[] queueIndex = new ArrayList[maxDrop + 1]; for (int k = 0; k < queueAccu.length; k++) { int drop = -queueAccu[k]; if (drop <= 0) continue; List<Integer> indexes = queueIndex[drop]; if (indexes == null) { indexes = new ArrayList<>(); queueIndex[-queueAccu[k]] = indexes; } indexes.add(k); } queuesForBoysIdx[j] = queueIndex; queuesForBoysAccum[j] = queueAccu; } long firstBancrupt = -1; long firstBancruptRounds = Long.MAX_VALUE; for (int j = 0; j < boysCount; j++) { int mod = j % differentCyclesForBoys; int offset = offsets[j % cycleLength]; long roundsToBancrupt = roundsForBoy(queuesForBoysIdx[mod], boys[j], queuesForBoysAccum[mod], offset); if (roundsToBancrupt != -1 && roundsToBancrupt < firstBancruptRounds) { firstBancruptRounds = roundsToBancrupt; firstBancrupt = j + 1; } } if (firstBancrupt == -1) { System.out.println("-1"); } else { long result = (firstBancruptRounds - 1) * boysCount + firstBancrupt; System.out.println(result); } } static long roundsForBoy(List<Integer>[] queueIndex, int start, int[] queueAccumulated, int offset) { if (offset == 0) return roundsForBoy(queueIndex, start, queueAccumulated); int offsetValue = queueAccumulated[offset - 1]; int maxDrop = queueIndex.length - 1; if (start - offsetValue <= maxDrop) { List<Integer> indexes = queueIndex[start - offsetValue]; int firstGeq = firstGeq(indexes, offset); if (firstGeq >= 0 ) { return firstGeq - offset + 1; } } int newStart = start - offsetValue + queueAccumulated[queueAccumulated.length - 1]; long roundsForNewStart = roundsForBoy(queueIndex, newStart, queueAccumulated); if (roundsForNewStart == -1) { return -1; } else { return queueAccumulated.length - offset + roundsForNewStart; } } static long roundsForBoy(List<Integer>[] queueIndex, int start, int[] queueAccumulated) { int queueSum = queueAccumulated[queueAccumulated.length - 1]; int maxDrop = queueIndex.length - 1; if (start <= maxDrop) { return queueIndex[start].get(0) + 1; } else if (queueSum >= 0) { return -1; } else { int fullCycles = (int) Math.ceil(((float) start - maxDrop) / -queueSum); int remaining = start + fullCycles * queueSum; return queueIndex[remaining].get(0) + 1L + (long)queueAccumulated.length * fullCycles; } } static int nwd(int a, int b) { if (b == 0) return a; else return nwd(b, a % b); } static long nww(int a, int b) { return ((long) a * b) / nwd(a, b); } static int firstGeq(List<Integer> list, int element) { int ins = Collections.binarySearch(list,element); if (ins >= 0) { return list.get(ins); } else if (ins == -list.size() - 1) { return -1; } else { return list.get(-ins-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 | import java.io.*; import java.util.*; public class haz { public static void main(String[] args) throws Exception { BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); int boysCount = Integer.parseInt(br.readLine()); int[] boys = new int[boysCount]; String boysString = br.readLine()+' '; int prevIdx = 0; for (int j = 0; j < boysCount; j++) { int idx = boysString.indexOf(' ', prevIdx); boys[j] = Integer.parseInt(boysString.substring(prevIdx, idx)); prevIdx = idx+1; } int cycleLength = Integer.parseInt(br.readLine()); int[] cycle = new int[cycleLength]; for (int j = 0; j < cycle.length; j++) { if (br.read() == 'W') { cycle[j] = 1; } else { cycle[j]= -1; } } int queueLen = (int) (nww(boysCount, cycleLength) / boysCount); int differentCyclesForBoys = cycleLength / queueLen; int[][] queuesForBoys = new int[differentCyclesForBoys][queueLen]; List<Integer>[][] queuesForBoysIdx = new List[differentCyclesForBoys][]; int[][] queuesForBoysAccum = new int[differentCyclesForBoys][cycleLength / differentCyclesForBoys]; int[] offsets = new int[cycleLength]; for (int j = 0; j < differentCyclesForBoys; j++) { for (int k = 0; k < queueLen; k++) { int value = (int) ((j + (long) k * boysCount) % cycleLength); queuesForBoys[j][k] = cycle[value]; offsets[value] = k; } } for (int j = 0; j < differentCyclesForBoys; j++) { int[] queue = queuesForBoys[j]; int[] queueAccu = new int[queue.length]; queueAccu[0] = queue[0]; int maxDrop = 0; for (int k = 1; k < queue.length; k++) { queueAccu[k] = queueAccu[k - 1] + queue[k]; maxDrop = Math.max(maxDrop, -queueAccu[k]); } List<Integer>[] queueIndex = new ArrayList[maxDrop + 1]; for (int k = 0; k < queueAccu.length; k++) { int drop = -queueAccu[k]; if (drop <= 0) continue; List<Integer> indexes = queueIndex[drop]; if (indexes == null) { indexes = new ArrayList<>(); queueIndex[-queueAccu[k]] = indexes; } indexes.add(k); } queuesForBoysIdx[j] = queueIndex; queuesForBoysAccum[j] = queueAccu; } long firstBancrupt = -1; long firstBancruptRounds = Long.MAX_VALUE; for (int j = 0; j < boysCount; j++) { int mod = j % differentCyclesForBoys; int offset = offsets[j % cycleLength]; long roundsToBancrupt = roundsForBoy(queuesForBoysIdx[mod], boys[j], queuesForBoysAccum[mod], offset); if (roundsToBancrupt != -1 && roundsToBancrupt < firstBancruptRounds) { firstBancruptRounds = roundsToBancrupt; firstBancrupt = j + 1; } } if (firstBancrupt == -1) { System.out.println("-1"); } else { long result = (firstBancruptRounds - 1) * boysCount + firstBancrupt; System.out.println(result); } } static long roundsForBoy(List<Integer>[] queueIndex, int start, int[] queueAccumulated, int offset) { if (offset == 0) return roundsForBoy(queueIndex, start, queueAccumulated); int offsetValue = queueAccumulated[offset - 1]; int maxDrop = queueIndex.length - 1; if (start - offsetValue <= maxDrop) { List<Integer> indexes = queueIndex[start - offsetValue]; int firstGeq = firstGeq(indexes, offset); if (firstGeq >= 0 ) { return firstGeq - offset + 1; } } int newStart = start - offsetValue + queueAccumulated[queueAccumulated.length - 1]; long roundsForNewStart = roundsForBoy(queueIndex, newStart, queueAccumulated); if (roundsForNewStart == -1) { return -1; } else { return queueAccumulated.length - offset + roundsForNewStart; } } static long roundsForBoy(List<Integer>[] queueIndex, int start, int[] queueAccumulated) { int queueSum = queueAccumulated[queueAccumulated.length - 1]; int maxDrop = queueIndex.length - 1; if (start <= maxDrop) { return queueIndex[start].get(0) + 1; } else if (queueSum >= 0) { return -1; } else { int fullCycles = (int) Math.ceil(((float) start - maxDrop) / -queueSum); int remaining = start + fullCycles * queueSum; return queueIndex[remaining].get(0) + 1L + (long)queueAccumulated.length * fullCycles; } } static int nwd(int a, int b) { if (b == 0) return a; else return nwd(b, a % b); } static long nww(int a, int b) { return ((long) a * b) / nwd(a, b); } static int firstGeq(List<Integer> list, int element) { int ins = Collections.binarySearch(list,element); if (ins >= 0) { return list.get(ins); } else if (ins == -list.size() - 1) { return -1; } else { return list.get(-ins-1); } } } |