Submission #826622

#	Time	Username	Problem	Language	Result	Execution time	Memory
826622		cig32	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	57 / 100	159 ms	262144 KiB

skyscraper

#include "bits/stdc++.h"
using namespace std;
#define double long double
const int MAXN = 9500000;
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;
}
int bm(int b, int p) {
  if(p==0) return 1 % MOD;
  int r = bm(b, p >> 1);
  if(p&1) return (((r*r) % MOD) * b) % MOD;
  return (r*r) % MOD;
}
int inv(int b) { 
  return bm(b, MOD-2);
}
int fastlog(int x) {
  return (x == 0 ? -1 : 64 - __builtin_clzll(x) - 1);
}
void printcase(int i) { cout << "Case #" << i << ": "; }
vector<pair<int, int> >adj[MAXN];
int n, m, s, nxt;
void construct(int b, int p) { 
  for(int j=b%p; j<n; j+=p) {
    if(j+p < n) adj[nxt + j/p].push_back({nxt + j/p + 1, 1});
    if(j-p >= 0) adj[nxt + j/p].push_back({nxt + j/p - 1, 1});
    adj[nxt + j/p].push_back({j, 0});
  }
  adj[b].push_back({nxt + b/p, 0});
  for(int j=b%p; j<n; j+=p) {
    nxt++;
  }
}
void solve(int tc) {
  cin >> n >> m;
  s = sqrt(n);
  nxt = n;
  int st, en;
  int bruh[s+1][s];
  for(int i=1; i<=s; i++) {
    for(int j=0; j<i; j++) {
      bruh[i][j] = -1;
    }
  }
  for(int i=0; i<m; i++) {
    int b, p;
    cin >> b >> p;
    if(i == 0) st = b;
    if(i == 1) en = b;
    if(p <= s && bruh[p][b%p] == -1) {
      bruh[p][b%p] = nxt;
      construct(b, p);
    }
    else if(p > s) {
      for(int j=b%p; j<n; j+=p) {
        if(b != j) adj[b].push_back({j, abs(b-j) / p});
      }
    }
    else {
      adj[b].push_back({bruh[p][b%p] + b/p, 0});
    }
  }
  int k = nxt;
  int dist[k];
  bool vis[k];
  for(int i=0; i<k; i++) dist[i] = 1e9, vis[i] = 0;
  dist[st] = 0;
  priority_queue<pair<int,int>, vector<pair<int,int> >,greater<pair<int,int> > >pq;
  pq.push({0, st});
  while(pq.size()) {
    pair<int, int> t = pq.top();
    pq.pop();
    if(!vis[t.second]) {
      if(t.second == en) break;
      vis[t.second] = 1;
      for(pair<int, int> x: adj[t.second]) {
        if(!vis[x.first] && dist[x.first] > dist[t.second] + x.second) {
          dist[x.first] = dist[t.second] + x.second;
          pq.push({dist[x.first], x.first});
        }
      }
    }
  }
  cout<<(dist[en]==1e9?-1:dist[en])<<"\n";
}
int32_t main() {
  ios::sync_with_stdio(0); cin.tie(0);
  int t = 1; //cin >> t;
  for(int i=1; i<=t; i++) solve(i);
}
// 勿忘初衷

Compilation message (stderr)

skyscraper.cpp: In function 'void solve(int)':
skyscraper.cpp:76:7: warning: 'en' may be used uninitialized in this function [-Wmaybe-uninitialized]
   76 |       if(t.second == en) break;
      |       ^~

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 14 / 14
• Subtask 4: 21 / 21
• Subtask 5: 0 / 43