Submission #45685

#	Time	Username	Problem	Language	Result	Execution time	Memory
45685		Trans	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	0 / 100	4 ms	3380 KiB

skyscraper

//https://oj.uz/problem/view/APIO15_skyscraper

#include <bits/stdc++.h>

using namespace std;

#define rep(i, a, b) for (int i = (a); i < (b); i++)
#define mp make_pair
#define fi first
#define se second
typedef pair<int, int> pii;

const int k = 200;
const int oo = 1e9 + 5;
const int maxn = 3e4 + 5;

int n, m, d[maxn], vs[maxn], ss, ee;
set<int> st[2][maxn];

int dij() {
  priority_queue<pii> heap;
  rep(i, 0, n) d[i] = oo;
  d[ss] = 0;
  heap.push(mp(0, ss));

  while (!heap.empty()) {
    pii cur = heap.top();
    cur.fi *= -1;
    if (cur.se == ee) return d[cur.se];
    // cout << "here " << cur.se << endl;
    heap.pop();
    // cout << cur.se << endl;
    if (vs[cur.se]) continue;
    vs[cur.se] = 1;

    for (auto it = st[0][cur.se].begin(); it != st[0][cur.se].end(); it++) {
      int jump = *it;
      int now = cur.se;
      assert(jump != 0);
      while (cur.se + jump < n) {
        int nxt = cur.se + jump;
        
        if (d[nxt] > cur.fi + 1) {
          d[nxt] = cur.fi + 1;
          heap.push(mp(-d[nxt], nxt));
          st[0][nxt].insert(jump);
        }
        if (st[0][nxt].find(jump) != st[0][nxt].end()) break;
        cur.se = nxt;
      }
      cur.se = now;

      while (cur.se - jump >= 0) {
        int pre = cur.se - jump;

        if (d[pre] > cur.fi + 1) {
          d[pre] = cur.fi + 1;
          heap.push(mp(-d[pre], pre));
          st[0][pre].insert(jump);
        }
        if (st[0][pre].find(jump) != st[0][pre].end()) break;
        cur.se = pre;
      }
      cur.se = now;
    }
  }

  return -1;
}

int main() {
  // freopen("inp.txt", "r", stdin);

  cin >> n >> m;

  rep(i, 0, m) {
    int x, y;
    cin >> x >> y;
    if (i == 0) ss = x;
    if (i == 1) ee = x;
    st[0][x].insert(y);
    // else st[1][x].insert(y);
  }

  cout << dij(); 

  return 0;
}

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