제출 #533183

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
533183		cig32	공장들 (JOI14_factories)	C++17	100 / 100	3614 ms	464008 KiB

factories

#include "factories.h"
#include "bits/stdc++.h"
using namespace std;
#define int long long
const int MOD = 1e9 + 7;
mt19937_64 rng((int)std::chrono::steady_clock::now().time_since_epoch().count());
int rnd(int x, int y) {
  int u = uniform_int_distribution<int>(x, y)(rng); return u;
}

void Init(int32_t N, int32_t A[], int32_t B[], int32_t D[]);
long long Query(int32_t S, int32_t X[], int32_t T, int32_t Y[]);

const int MAXN = 500003;
vector<pair<int, int> > adj[MAXN];

pair<int, signed> st[20][2*MAXN];

int tin[MAXN], tout[MAXN], cur = 0;
int dep[MAXN];
int l[MAXN], r[MAXN];
vector<int> e;
void dfs(int node, int prv, int ohno) {
  tin[node] = ++cur;
  dep[node] = ohno;
  e.push_back(node);
  for(auto x: adj[node]) {
    if(x.first != prv) {
      dfs(x.first, node, ohno + x.second);
      e.push_back(node);
    }
  }
  tout[node] = ++cur;
}

int lca_dep(int x, int y) {
  int m1 = min(l[x], l[y]), m2 = max(r[x], r[y]);
  int k = 32 - __builtin_clz(m2 - m1 + 1) - 1;
  return min(st[k][m1], st[k][m2 - (1<<k) + 1]).first;
}

int dist(int x, int y) {
  return dep[x] + dep[y] - 2 * lca_dep(x, y);
}

int lca_idx(int x, int y) {
  int m1 = min(l[x], l[y]), m2 = max(r[x], r[y]);
  int k = 32 - __builtin_clz(m2 - m1 + 1) - 1;
  return min(st[k][m1], st[k][m2 - (1<<k) + 1]).second;
}


int miS[MAXN], miT[MAXN];

void Init(int32_t N, int32_t A[], int32_t B[], int32_t D[]) {
  for(int i=0; i<N; i++) {
    miS[i] = miT[i] = 1e18;
  }
  for(int i=0; i<N-1; i++) {
    adj[A[i]].push_back({B[i], D[i]});
    adj[B[i]].push_back({A[i], D[i]});
  }
  dfs(0, -1, 0);
  for(int i=0; i<e.size(); i++) {
    r[e[i]] = i;
  }
  for(int i=e.size()-1; i>=0; i--) {
    l[e[i]] = i;
  }
  for(int i=0; i<e.size(); i++) st[0][i] = {dep[e[i]], e[i]};
  for(int i=1; i<20; i++) {
    for(int j=0; j<e.size(); j++) {
      if(j + (1<<i) - 1 < e.size()) {
        st[i][j] = min(st[i-1][j], st[i-1][j + (1<<(i-1))]);
      }
    }
  }
}

bool dfs_order(int a, int b) {
  return tin[a] < tin[b];
}

vector<int> adj2[MAXN]; 

char grp[MAXN]; 

int dpf(int node, int prv) {
  int ans = 1e18;
  for(int x: adj2[node]) {
    if(x != prv) {
      ans = min(ans, dpf(x, node));
      miS[node] = min(miS[node], miS[x]);
      miT[node] = min(miT[node], miT[x]);
    }
  }
  if(grp[node] == 'S') {
    miS[node] = dep[node];
  }
  else if(grp[node] == 'T') {
    miT[node] = dep[node];
  }
  ans = min(ans, miS[node] + miT[node] - 2 * dep[node]);
  return ans;
}

long long Query(int32_t S, int32_t X[], int32_t T, int32_t Y[]) {
  vector<int> v;
  for(int i=0; i<S; i++) {
    v.push_back(X[i]);
    grp[X[i]] = 'S';
  }
  for(int i=0; i<T; i++) {
    v.push_back(Y[i]);
    grp[Y[i]] = 'T';
  }
  sort(v.begin(), v.end(), dfs_order);
  unordered_map<int, int> here;
  for(int x: v) here[x] = 1;
  int V = v.size();
  for(int i=1; i<V; i++) {
    int lol = lca_idx(v[i], v[i-1]);
    if(!here[lol]) {
      here[lol] = 1;
      v.push_back(lol);
      grp[lol] = 'L';
    }
  }
  sort(v.begin(), v.end(), dfs_order);
  stack<int> st;
  for(int x: v) {
    adj2[x].clear();
    miS[x] = miT[x] = 1e18;
  }
  int rt;
  for(int x: v) {
    while(st.size() && !(tin[st.top()] < tin[x] && tout[x] < tout[st.top()])) {
      st.pop();
    }
    if(st.size()) {
      adj2[st.top()].push_back(x);
    }
    else {
      rt = x;
    }
    st.push(x);
  }
  return dpf(rt, -1);
}

컴파일 시 표준 에러 (stderr) 메시지

factories.cpp: In function 'void Init(int32_t, int32_t*, int32_t*, int32_t*)':
factories.cpp:64:17: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   64 |   for(int i=0; i<e.size(); i++) {
      |                ~^~~~~~~~~
factories.cpp:70:17: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   70 |   for(int i=0; i<e.size(); i++) st[0][i] = {dep[e[i]], e[i]};
      |                ~^~~~~~~~~
factories.cpp:72:19: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   72 |     for(int j=0; j<e.size(); j++) {
      |                  ~^~~~~~~~~
factories.cpp:73:25: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   73 |       if(j + (1<<i) - 1 < e.size()) {
      |          ~~~~~~~~~~~~~~~^~~~~~~~~~
factories.cpp: In function 'long long int Query(int32_t, int32_t*, int32_t, int32_t*)':
factories.cpp:148:13: warning: 'rt' may be used uninitialized in this function [-Wmaybe-uninitialized]
  148 |   return dpf(rt, -1);
      |          ~~~^~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 18 / 18
• Subtask 3: 67 / 67