제출 #280126

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
280126		Haunted_Cpp	Hotspot (NOI17_hotspot)	C++17	38 / 100	346 ms	524292 KiB

hotspot

/**
 *  author: Haunted_Cpp
**/
 
#include <bits/stdc++.h>
using namespace std;
 
#pragma GCC optimize("Ofast")
#pragma GCC target("fma,sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")
#pragma GCC optimize("unroll-loops")
 
template<typename T> ostream &operator << (ostream &os, const vector<T> &v) { os << '{'; string sep; for (const auto &x : v) os << sep << x, sep = ", "; return os << '}'; }
template<typename T, size_t size> ostream &operator << (ostream &os, const array<T, size> &arr) { os << '{'; string sep; for (const auto &x : arr) os << sep << x, sep = ", "; return os << '}'; }
template<typename A, typename B> ostream &operator << (ostream &os, const pair<A, B> &p) { return os << '(' << p.first << ", " << p.second << ')'; }
 
void debug_out() { cerr << endl; }
template<typename Head, typename... Tail> void debug_out(Head H, Tail... T) { cerr << ' ' << H; debug_out(T...); }
 
#ifdef LOCAL
#define debug(...) cerr << "(" << #__VA_ARGS__ << "):", debug_out(__VA_ARGS__)
#else
#define debug(...) 47
#endif

const int MAX_N = 1e3 + 5;
const int MAX_K = 20 + 5;

vector<vector<int>> dp(MAX_N, vector<int>(MAX_K, -1));
vector<vector<int>> g(MAX_N);

vector<int> h(MAX_N), depth(MAX_N);
vector<int> sum(MAX_N);

void dfs(int node, int p) {
  dp[node][0] = p;
  for (auto to : g[node]) {
    if (to != p) {
      depth[to] = depth[node] + 1;
      dfs(to, node);
    }
  }
}

int kth(int node, int diff) {
  for (int i = MAX_K - 1; ~i; i--) {
    if ((diff >> i) & 1) {
      node = dp[node][i];
    }
  }
  return node;
}

int lca(int u, int v) {
  if (depth[u] < depth[v]) swap(u, v);
  u = kth(u, depth[u] - depth[v]);
  if (u == v) return u;
  for (int i = MAX_K - 1; ~i; i--) {
    if (dp[u][i] != dp[v][i]) {
      u = dp[u][i];
      v = dp[v][i];
    }
  }
  return dp[u][0];
}

int solve(int node, int p) {
  for (auto to : g[node]) {
    if (to != p) {
      sum[node] += solve(to, node);
    }
  } 
  debug(node, sum[node]);
  return sum[node];
}


int main() {
  ios::sync_with_stdio(0);
  cin.tie(0); 
  int n, m;
  cin >> n >> m;
  for (int i = 0; i < m; i++) {
    int st, et;
    cin >> st >> et;
    g[st].emplace_back(et);
    g[et].emplace_back(st);
  }
  dfs(0, -1);
  for(int j = 1; j < MAX_K; j++) {
    for (int i = 0; i < n; i++) {
      if (~dp[i][j - 1]) {
        dp[i][j] = dp[dp[i][j - 1]][j - 1];
      }
    }
  }
  int k;
  cin >> k;
  while(k--) {
    int st, et;
    cin >> st >> et;
    ++sum[st];
    ++sum[et];
    debug(st, et);
    int LCA = lca(st, et);
    if (LCA != -1) {
      sum[LCA] -= 1;
    }
    LCA = dp[LCA][0];
    if (LCA != -1) {
      sum[LCA] -= 1;
    }
  }
  solve(0, -1);
  cout << (max_element(sum.begin(), sum.end()) - sum.begin()) << '\n';
  return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

hotspot.cpp: In function 'int solve(int, int)':
hotspot.cpp:22:20: warning: statement has no effect [-Wunused-value]
   22 | #define debug(...) 47
      |                    ^~
hotspot.cpp:72:3: note: in expansion of macro 'debug'
   72 |   debug(node, sum[node]);
      |   ^~~~~
hotspot.cpp: In function 'int main()':
hotspot.cpp:22:20: warning: statement has no effect [-Wunused-value]
   22 | #define debug(...) 47
      |                    ^~
hotspot.cpp:103:5: note: in expansion of macro 'debug'
  103 |     debug(st, et);
      |     ^~~~~

• Subtask 1: 4 / 4
• Subtask 2: 5 / 5
• Subtask 3: 11 / 11
• Subtask 4: 18 / 18
• Subtask 5: 0 / 26
• Subtask 6: 0 / 36