Advertisement
Not a member of Pastebin yet?
Sign Up,
it unlocks many cool features!
- #include <iostream>
- #include <random>
- #include <vector>
- #include <algorithm>
- using namespace std;
- const int INF = 100000;
- const int MAXN = 3001;
- int tries = 15000;
- int cnt = 100;
- struct point{
- int x, y;
- double operator-(point& oth) {
- return sqrt((x - oth.x) * (x - oth.x) + (y - oth.y) * (y - oth.y));
- }
- };
- point a[MAXN];
- double get_dist(vector<int>& ind) {
- double d = (a[0] - a[ind[0]]) + (a[ind.back()] - a[0]);
- for (int i = 1; i < ind.size(); ++i) {
- d += (a[ind[i]] - a[ind[i - 1]]);
- }
- return d;
- }
- vector<int> v;
- double get_mistakes() {
- double d = (a[0] - a[v[0]]) + (a[v.back()] - a[0]);
- for (int i = 1; i < v.size(); ++i) {
- d += (a[v[i]] - a[v[i - 1]]);
- }
- return d;
- }
- void reverse(int x, int y) {
- int len = y - x + 1;
- for (int i = x, cnt = 0; i < x + len/2; ++i, ++cnt) {
- swap(v[i], v[y - cnt]);
- }
- }
- int main() {
- std::ios_base::sync_with_stdio(false), cin.tie(0), cout.tie(0);
- srand(time(NULL));
- int n;
- cin >> n;
- vector<int> start_state;
- for (int i = 0; i < n; ++i) {
- cin >> a[i].x >> a[i].y;
- if (i > 0) {
- start_state.push_back(i);
- }
- }
- double energy = get_dist(start_state);
- double start_energy = energy;
- double temp = 20.0;
- double ans = energy;
- vector<int> ans_vect;
- int sz = start_state.size();
- while (cnt--) {
- v = start_state;
- for (int k = 1; k <= tries; k++) {
- int x = rand() % sz;
- int y = rand() % sz;
- while (x == y) {
- y = rand() % sz;
- }
- if (x > y) {
- swap(x, y);
- }
- reverse(x, y);
- double mistakes = get_mistakes();
- if (mistakes > energy) {
- double p = exp(-(mistakes - energy)/temp);
- if (p > 1.0 * (rand() % (INF + 1)) / INF) {
- energy = mistakes;
- } else {
- }
- }
- energy = min(energy, mistakes);
- temp = 0.99 * temp / k;
- if (energy < ans) {
- ans = energy;
- ans_vect = v;
- }
- }
- energy = start_energy;
- temp = 20;
- }
- cout << "1 ";
- for (auto x : ans_vect) {
- cout << x + 1 << " ";
- }
- cout << 1;
- return 0;
- }
Advertisement
Add Comment
Please, Sign In to add comment
Advertisement