#include <cstdio> #include <algorithm> #include <vector> #include "kanapka.h" #include "message.h" struct Data { long long Sum, MaxL, MaxR, Best; }; static void printData(const Data &data) { // printf("{ .Sum=%lld .MaxL=%lld .MaxR=%lld .Best=%lld }\n", // data.Sum, data.MaxL, data.MaxR, data.Best); } static void getMyValues(std::vector<int> &V) { assert(V.empty()); int n = GetN(); int nodes = (int)NumberOfNodes(); int X = n / nodes; V.reserve(X + 4); int E; if (MyNodeId() == nodes - 1) E = n; else E = (MyNodeId() * X) + X; for (int i = MyNodeId() * X; i < E; ++i) { int v = GetTaste(i); // printf("[%d] gets %d\n", MyNodeId(), v); V.push_back(v); } } static const Data getMyData(const std::vector<int> &V) { std::vector<long long> MaxR(V.size()); long long currR = 0; long long tmpR = 0; for (int i = V.size() - 1; i >= 0; --i) { currR += V[i]; MaxR[i] = tmpR = std::max(currR, tmpR); } long long currL = 0; long long tmpL = 0; long long best = 0; for (int i = 0; i < V.size(); ++i) { currL += V[i]; // imporant, do it before tmpL is computed best = std::max(best, tmpL + MaxR[i]); tmpL = std::max(currL, tmpL); } assert(currL == currR); Data data; data.Sum = currL; data.MaxL = tmpL; data.MaxR = tmpR; data.Best = best; return data; } int main() { std::vector<int> V; getMyValues(V); const Data myData = getMyData(V); if (MyNodeId()) { PutLL(0, myData.Sum); PutLL(0, myData.MaxL); PutLL(0, myData.MaxR); PutLL(0, myData.Best); Send(0); return 0; } const int nodes = (int)NumberOfNodes(); Data *data = new Data[nodes]; data[0] = myData; // printf("data[0] = "); printData(data[0]); for (int i = 1; i < nodes; ++i) { Receive(i); data[i].Sum = GetLL(i); data[i].MaxL = GetLL(i); data[i].MaxR = GetLL(i); data[i].Best = GetLL(i); // printf("data[%d] = ", i); printData(data[i]); } long long *maxR = new long long[nodes]; long long *valR = new long long[nodes]; long long currR = 0; long long tmpR = 0; for (int i = nodes - 1; i >= 0; --i) { long long oldR = currR; currR += data[i].Sum; valR[i] = currR; maxR[i] = tmpR = std::max(tmpR, oldR + data[i].MaxR); // printf("maxR[%d] = %lld\n", i, maxR[i]); } long long valL = 0; long long maxL = 0; long long best = 0; for (int i = 0; i < nodes; ++i) { long long v1 = valL + data[i].Best + (i < nodes - 1 ? valR[i+1] : 0); long long v2 = valL + data[i].MaxL + (i < nodes - 1 ? maxR[i+1] : 0); long long v3 = maxL + data[i].MaxR + (i < nodes - 1 ? valR[i+1] : 0); long long v4 = maxL + 0 + (i < nodes - 1 ? maxR[i+1] : 0); // printf("%d: maxL=%lld valL=%lld v1=%lld v2=%lld v3=%lld v4=%lld\n", // i, maxL, valL, v1, v2, v3, v4); best = std::max(best, v1); best = std::max(best, v2); best = std::max(best, v3); best = std::max(best, v4); valL += data[i].Sum; maxL = std::max(valL, maxL); } printf("%lld\n", best); }
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 | #include <cstdio> #include <algorithm> #include <vector> #include "kanapka.h" #include "message.h" struct Data { long long Sum, MaxL, MaxR, Best; }; static void printData(const Data &data) { // printf("{ .Sum=%lld .MaxL=%lld .MaxR=%lld .Best=%lld }\n", // data.Sum, data.MaxL, data.MaxR, data.Best); } static void getMyValues(std::vector<int> &V) { assert(V.empty()); int n = GetN(); int nodes = (int)NumberOfNodes(); int X = n / nodes; V.reserve(X + 4); int E; if (MyNodeId() == nodes - 1) E = n; else E = (MyNodeId() * X) + X; for (int i = MyNodeId() * X; i < E; ++i) { int v = GetTaste(i); // printf("[%d] gets %d\n", MyNodeId(), v); V.push_back(v); } } static const Data getMyData(const std::vector<int> &V) { std::vector<long long> MaxR(V.size()); long long currR = 0; long long tmpR = 0; for (int i = V.size() - 1; i >= 0; --i) { currR += V[i]; MaxR[i] = tmpR = std::max(currR, tmpR); } long long currL = 0; long long tmpL = 0; long long best = 0; for (int i = 0; i < V.size(); ++i) { currL += V[i]; // imporant, do it before tmpL is computed best = std::max(best, tmpL + MaxR[i]); tmpL = std::max(currL, tmpL); } assert(currL == currR); Data data; data.Sum = currL; data.MaxL = tmpL; data.MaxR = tmpR; data.Best = best; return data; } int main() { std::vector<int> V; getMyValues(V); const Data myData = getMyData(V); if (MyNodeId()) { PutLL(0, myData.Sum); PutLL(0, myData.MaxL); PutLL(0, myData.MaxR); PutLL(0, myData.Best); Send(0); return 0; } const int nodes = (int)NumberOfNodes(); Data *data = new Data[nodes]; data[0] = myData; // printf("data[0] = "); printData(data[0]); for (int i = 1; i < nodes; ++i) { Receive(i); data[i].Sum = GetLL(i); data[i].MaxL = GetLL(i); data[i].MaxR = GetLL(i); data[i].Best = GetLL(i); // printf("data[%d] = ", i); printData(data[i]); } long long *maxR = new long long[nodes]; long long *valR = new long long[nodes]; long long currR = 0; long long tmpR = 0; for (int i = nodes - 1; i >= 0; --i) { long long oldR = currR; currR += data[i].Sum; valR[i] = currR; maxR[i] = tmpR = std::max(tmpR, oldR + data[i].MaxR); // printf("maxR[%d] = %lld\n", i, maxR[i]); } long long valL = 0; long long maxL = 0; long long best = 0; for (int i = 0; i < nodes; ++i) { long long v1 = valL + data[i].Best + (i < nodes - 1 ? valR[i+1] : 0); long long v2 = valL + data[i].MaxL + (i < nodes - 1 ? maxR[i+1] : 0); long long v3 = maxL + data[i].MaxR + (i < nodes - 1 ? valR[i+1] : 0); long long v4 = maxL + 0 + (i < nodes - 1 ? maxR[i+1] : 0); // printf("%d: maxL=%lld valL=%lld v1=%lld v2=%lld v3=%lld v4=%lld\n", // i, maxL, valL, v1, v2, v3, v4); best = std::max(best, v1); best = std::max(best, v2); best = std::max(best, v3); best = std::max(best, v4); valL += data[i].Sum; maxL = std::max(valL, maxL); } printf("%lld\n", best); } |