Submission #1013529

#TimeUsernameProblemLanguageResultExecution timeMemory
1013529spacewalkerIdeal city (IOI12_city)C++14
Compilation error
0 ms0 KiB
#include <bits/stdc++.h> using namespace std; using ll = long long; constexpr ll MOD = 1'000'000'000; struct Segment { int x, y1, y2; Segment(int x, int y1, int y2) : x(x), y1(y1), y2(y2) {} }; ostream& operator << (ostream& os, const Segment &s) { return os << "[x = " << s.x << "; y = " << s.y1 << "..." << s.y2 << "]"; } bool adjacent(const Segment &a, const Segment &b) { return abs(a.x - b.x) <= 1 && max(a.y1, b.y1) <= min(a.y2, b.y2); } vector<Segment> divide_into_segments(const vector<pair<int, int>> &blocks) { vector<Segment> segments; optional<Segment> currentSegment; for (int i = 0; i < blocks.size(); ++i) { if (!currentSegment) currentSegment = Segment(blocks[i].first, blocks[i].second, blocks[i].second); else if (currentSegment->x != blocks[i].first || currentSegment->y2 + 1 < blocks[i].second) { segments.push_back(*currentSegment); currentSegment = Segment(blocks[i].first, blocks[i].second, blocks[i].second); } else { currentSegment->y2 = blocks[i].second; } } if (currentSegment) segments.push_back(*currentSegment); return segments; } ll pair_distance_sum(const vector<ll> &points) { if (points.size() == 0) { return 0; } ll ans = 0; ll total = accumulate(points.begin(), points.end(), 0LL); ll right_side = 0; for (int i = 0; i < points.size(); ++i) { right_side += points[i]; ans += right_side * (total - right_side) % MOD; } /* cerr << "PDS " << ans; for (ll v : points) cerr << " " << v; cerr << endl; */ return ans % MOD; } vector<vector<ll>> segments_reachable; ll sum_of_distances(int n, const vector<vector<int>> &tree, const vector<Segment> &segs, int v, int p) { auto cseg = segs[v]; int length = cseg.y2 - cseg.y1 + 1; segments_reachable[v].assign(length, 1); auto comp = [&] (int y) { return clamp(y, cseg.y1, cseg.y2) - cseg.y1; }; ll ans = 0; for (int child : tree[v]) { if (child == p) continue; ans += sum_of_distances(n, tree, segs, child, v); int comp_min = comp(segs[child].y1), comp_max = comp(segs[child].y2); vector<ll> csubsegment(comp_max - comp_min + 1); ll segments_in_child = accumulate(segments_reachable[child].begin(), segments_reachable[child].end(), 0LL); for (int y = segs[child].y1; y <= segs[child].y2; ++y) { ll segments_here = segments_reachable[child][y - segs[child].y1]; segments_reachable[v][comp(y)] += segments_here; csubsegment[comp(y) - comp_min] += segments_here; ll delta_y = abs(y - clamp(y, cseg.y1, cseg.y2)) + 1; ans += delta_y * segments_here % MOD * (n - segments_in_child) % MOD; } ans -= pair_distance_sum(csubsegment); } ans += pair_distance_sum(segments_reachable[v]); ans = (ans % MOD + MOD) % MOD; // cerr << "SOD " << v << " (par " << p << " " << segs[v] << ") ans " << ans << endl; return ans; } int DistanceSum(int N, int *X, int *Y) { segments_reachable.assign(N, vector<ll>()); vector<pair<int, int>> blocks(N); for (int i = 0; i < N; ++i) blocks[i] = {X[i], Y[i]}; sort(blocks.begin(), blocks.end()); auto segments = divide_into_segments(blocks); // for (auto &s : segments) cerr << s << endl; int k = segments.size(); vector<vector<int>> tree(k); for (int i = 0, j = 0, prev = 0; i < k; prev = i, i = j) { while (j < k && segments[j].x == segments[i].x) ++j; int cprev = prev; for (int cseg_i = i; cseg_i < j; ++cseg_i) { while (cprev < i && segments[cprev].y2 < segments[cseg_i].y1) ++cprev; while (cprev < i && adjacent(segments[cseg_i], segments[cprev])) { // cerr << "adjacent " << segments[cseg_i] << " " << segments[cprev] << endl; tree[cseg_i].push_back(cprev); tree[cprev].push_back(cseg_i); if (segments[cprev].y2 <= segments[cseg_i].y1) { ++cprev; } else { break; } } } } return sum_of_distances(N, tree, segments, 0, -1); }

Compilation message (stderr)

city.cpp: In function 'std::vector<Segment> divide_into_segments(const std::vector<std::pair<int, int> >&)':
city.cpp:23:3: error: 'optional' was not declared in this scope
   23 |   optional<Segment> currentSegment;
      |   ^~~~~~~~
city.cpp:23:3: note: 'std::optional' is only available from C++17 onwards
city.cpp:23:19: error: expected primary-expression before '>' token
   23 |   optional<Segment> currentSegment;
      |                   ^
city.cpp:23:21: error: 'currentSegment' was not declared in this scope
   23 |   optional<Segment> currentSegment;
      |                     ^~~~~~~~~~~~~~
city.cpp:24:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |   for (int i = 0; i < blocks.size(); ++i) {
      |                   ~~^~~~~~~~~~~~~~~
city.cpp: In function 'll pair_distance_sum(const std::vector<long long int>&)':
city.cpp:44:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   44 |   for (int i = 0; i < points.size(); ++i) {
      |                   ~~^~~~~~~~~~~~~~~
city.cpp: In lambda function:
city.cpp:64:12: error: 'clamp' was not declared in this scope
   64 |     return clamp(y, cseg.y1, cseg.y2) - cseg.y1;
      |            ^~~~~
city.cpp: In function 'll sum_of_distances(int, const std::vector<std::vector<int> >&, const std::vector<Segment>&, int, int)':
city.cpp:72:28: error: 'comp_max' was not declared in this scope; did you mean 'comp_min'?
   72 |     vector<ll> csubsegment(comp_max - comp_min + 1);
      |                            ^~~~~~~~
      |                            comp_min
city.cpp:80:28: error: 'clamp' was not declared in this scope
   80 |       ll delta_y = abs(y - clamp(y, cseg.y1, cseg.y2)) + 1;
      |                            ^~~~~