#line 1 "test.cpp" #define PROBLEM "https://yukicoder.me/problems/no/705" #line 2 "https://drken1215.github.io/algorithm/Optimization/dd_monotone_minima.hpp.html" #include #line 4 "https://drken1215.github.io/algorithm/Optimization/dd_monotone_minima.hpp.html" using namespace std; #line 4 "https://drken1215.github.io/algorithm/Optimization/monotone_minima.hpp.html" using namespace std; // find min_j f(i, j) for all i, by Monotone Minima, O(H + W log H) // f(i, j) must be monotone (argmin is not decreasing) // slide access OK template void MonotoneMinimaRec (int HL, int HR, int WL, int WR, const FUNC &f, vector> &res) { if (HR - HL <= 0) return; int HM = (HL + HR) / 2; res[HM].second = WL; for (int i = WL; i < WR; i++) { VAL val = f(HM, i); if (res[HM].first > val) res[HM] = make_pair(val, i); } MonotoneMinimaRec(HL, HM, WL, res[HM].second + 1, f, res); MonotoneMinimaRec(HM + 1, HR, res[HM].second, WR, f, res); } template vector> MonotoneMinima(int H, int W, const FUNC &f) { vector> res(H, make_pair(numeric_limits::max() / 2, -1)); MonotoneMinimaRec(0, H, 0, W, f, res); return res; } #line 7 "https://drken1215.github.io/algorithm/Optimization/dd_monotone_minima.hpp.html" // find shortest path on DAG by D&D Monotone Minima, O(N (log N)^2) // vertex: 0, 1, 2, ..., N // A(j, i) = dp[i] + f(i, j) must be monotone (argmin is not decreasing) // Attention: Even if f is monotone, A is not necessarily monotone // slide access OK template struct DDMonotoneMinima { VAL INF = numeric_limits::max() / 2; int CNT_INF = numeric_limits::max() / 2; // results vector dp; vector cnt, prev; // solver template vector> solve(int N, const FUNC &f) { dp.assign(N + 1, INF); cnt.assign(N + 1, CNT_INF); prev.assign(N + 1, 0); dp[0] = 0, cnt[0] = 0; vector> res(N + 1, make_pair(numeric_limits::max() / 2, -1)); res[0].first = VAL(0); auto f2 = [&](int i, int j) -> VAL { return res[j].first + f(j, i); }; auto rec = [&](auto &&rec, int left, int right) -> void { if (right - left <= 1) return; int mid = (left + right) / 2; rec(rec, left, mid); MonotoneMinimaRec(mid, right, left, mid, f2, res); rec(rec, mid, right); }; rec(rec, 0, N + 1); for (int r = 1; r <= N; r++) { dp[r] = res[r].first; prev[r] = res[r].second; if (prev[r] != -1) cnt[r] = cnt[prev[r]] + 1; } return res; } // reconstruct the shortest path vector reconstruct() { int N = (int)dp.size() - 1; vector path; for (int v = N; v > 0; v = prev[v]) path.emplace_back(v); path.emplace_back(0); reverse(path.begin(), path.end()); return path; } }; #line 4 "test.cpp" // yukicoder No.705 ゴミ拾い Hard /* A, X, Y: N 個 これらを区間に分割していく  dp[j] = min_{0 ≦ i < j}(dp[i] + |A[j-1] - X[i]|^3 + |-Y[i]|^3) i -> j のコスト:|A[j-1] - X[i]|^3 + |-Y[i]|^3 ...... 差の凸関数 (Monge) + 縞々 (Monge) -> Monge スタート: 0, ゴール: N */ int main() { int N; cin >> N; vector A(N), X(N), Y(N); for (int i = 0; i < N; i++) cin >> A[i]; for (int i = 0; i < N; i++) cin >> X[i]; for (int i = 0; i < N; i++) cin >> Y[i]; auto func = [&](int i, int j) -> long long { long long dx = abs(A[j-1] - X[i]), dy = abs(Y[i]); return dx * dx * dx + dy * dy * dy; }; DDMonotoneMinima opt; auto res = opt.solve(N, func); cout << res[N].first << endl; }