#include "../util.h" constexpr ll iINFnf = LL::INF; #include vector> gen(int n) { vector> res(n, vector(n)); ll mi = 0; for (ll a = n-1; a >= 0; a--) { for (ll c = n-1; c >= a; c--) { for (ll b = a; b <= c; b++) { for (ll d = c; d < n; d++) { res[a][c] = min(res[a][c], res[a][d] + res[b][c] - res[b][d]); } } res[a][c] -= Random::integer(0, 1000); mi = min(mi, res[a][c]); } } for (auto& v : res) for (auto& x : v) x -= mi; for (ll a = 0; a < n; a++) { for (ll b = a; b < n; b++) { for (ll c = b; c < n; c++) { for (ll d = c; d < n; d++) { if (res[a][d] < 0 || res[a][d] + res[b][c] < res[a][c] + res[b][d]) { cerr << "invalid C array!" << FAIL; } } } } } return res; } vector> genQuick(int n) { vector> res(n, vector(n)); for (ll a = n-1; a >= 0; a--) { for (ll c = n-1; c >= a; c--) { res[a][c] = (c-a) * (c - a) + Random::integer(0, 2); } } return res; } /*ll naive(int n, int m, const vector>& C) { vector> state(m+1, vector(n+1, INF)); state[0][0] = 0; for (int i = 1; i <= m; i++) { for (int j = 1; j <= n; j++) { for (int k = 1; k <= j; k++) { state[i][j] = min(state[i][j], state[i-1][k-1] + C[k-1][j-1]); } } } return state[m][n]; }*/ vector naive(int n, const vector>& C) { vector> state(n+1, vector(n+1, INF)); state[0][0] = 0; vector res(n+1, INF); for (int i = 1; i <= n; i++) { for (int j = 1; j <= n; j++) { for (int k = 1; k <= j; k++) { state[i][j] = min(state[i][j], state[i-1][k-1] + C[k-1][j-1]); } } res[i] = state[i][n]; } return res; } void stress_test() { ll tests = 0; for (ll i = 0; i < 1000; i++) { auto n = Random::integer(10, 20); auto C = gen(n); auto expected = naive(n, C); for (ll m = 1; m <= n; m++) { auto got = calc(n, m, C); if (got != expected[m]) cerr << "got: " << got << ", expected: " << expected[m] << FAIL; tests++; } } cerr << "tested random queries: " << tests << endl; } constexpr int N = 5000; void performance_test() { timer t; auto C = genQuick(N); t.start(); auto hash = calc(N, N/2, C); t.stop(); if (t.time > 500) cerr << "too slow: " << t.time << FAIL; cerr << "tested performance: " << t.time << "ms (hash: " << hash << ")" << endl; } int main() { stress_test(); performance_test(); }