Submission #882773

#	Time	Username	Problem	Language	Result	Execution time	Memory
882773		mychecksedad	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	100 / 100	244 ms	135252 KiB

skyscraper

/* Author : Mychecksdead  */
#include<bits/stdc++.h>
using namespace std;
#define ll long long int
#define MOD (1000000000+7)
#define MOD1 (998244353)
#define pb push_back
#define all(x) x.begin(), x.end()
#define en cout << '\n'
const int N = 1e6+100, M = 1e5+10, K = 52, MX = 30;


int n, m;
vector<pair<int, int>> g[N];
bitset<30005> vis[30005];
vector<bool> VIS(N);
void solve(){ 
  cin >> n >> m;
  int z = 0, aim;
  for(int i = 1; i <= m; ++i){
    int b, p; cin >> b >> p;
    if(i==1) z = b;
    if(i==2) aim = b;
    g[b].pb({i, p});
  }
  deque<array<int, 3>> q;
  for(auto x: g[z]) q.pb({0, z, x.second}), vis[z][x.second] = 1;
  VIS[z] = 1;
  while(!q.empty()){
    auto v = q.front(); q.pop_front();
    // cout << v[0] << ' ' << v[1] << ' ' << v[2] << '\n';
    if(!VIS[v[1]]){
      VIS[v[1]] = 1;
      for(auto x: g[v[1]]){
        q.push_front({v[0], v[1], x.second});
        vis[v[1]][x.second] = 1;
      }
    }
    if(v[1] == aim){
      cout << v[0];
      return;
    }
    if(v[1] - v[2] >= 0 && !vis[v[1] - v[2]][v[2]]){
      vis[v[1] - v[2]][v[2]] = 1;
      q.pb({v[0] + 1, v[1] - v[2], v[2]});
    }
    if(v[1] + v[2] < n && !vis[v[1] + v[2]][v[2]]){
      vis[v[1] + v[2]][v[2]] = 1;
      q.pb({v[0] + 1, v[1] + v[2], v[2]});
    }
  }
  cout << -1;
}



int main(){
  cin.tie(0); ios::sync_with_stdio(0);
  int tt = 1, aa;
  // freopen("in.txt", "r", stdin);
  // freopen("out.txt", "w", stdout);
  while(tt--){
    solve();
    en;
  }
  cerr<<"time taken : "<<(float)clock()/CLOCKS_PER_SEC<<" seconds\n";
  return 0;
} 

Compilation message (stderr)

skyscraper.cpp: In function 'int main()':
skyscraper.cpp:59:15: warning: unused variable 'aa' [-Wunused-variable]
   59 |   int tt = 1, aa;
      |               ^~
skyscraper.cpp: In function 'void solve()':
skyscraper.cpp:39:5: warning: 'aim' may be used uninitialized in this function [-Wmaybe-uninitialized]
   39 |     if(v[1] == aim){
      |     ^~

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