Submission #927161

#	Time	Username	Problem	Language	Result	Execution time	Memory
927161		Amirreza_Fakhri	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	57 / 100	56 ms	9652 KiB

skyscraper

// In the name of the God
#include <bits/stdc++.h>
#define ll long long
// #define int long long
#define pb push_back
#define F first
#define S second
#define mp make_pair
#define pii pair <int, int>
#define smin(x, y) (x) = min((x), (y))
#define smax(x, y) (x) = max((x), (y))
#define all(x) (x).begin(), (x).end()
using namespace std;

const int inf = 1e9+7;
const int mod = 998244353;
const int maxn = 3e4+5;

int n, m, s, t, cnt = 0, dist[maxn];
set <int> doge[maxn];
set <pii> st;

void dij(int v) {
    fill(dist, dist+n, inf);
    dist[v] = 0;
    st.insert(mp(0, v));
    while (st.size()) {
        int d = st.begin()->F, u = st.begin()->S;
        st.erase(st.begin());
        // if (u == t) return cout << d << '\n', void();
        for (int p : doge[u]) {
            for (int j = 1; u+j*p < n; j++) {
                if (dist[u+j*p] > d+j) {
                    st.erase(mp(dist[u+j*p], u+j*p));
                    dist[u+j*p] = d+j;
                    st.insert(mp(d+j, u+j*p));
                }
                cnt++;
                assert(cnt < 1000*1000);
                if (doge[u+j*p].find(p) != doge[u+j*p].end()) break;
            }
            for (int j = 1; u-j*p >= 0; j++) {
                if (dist[u-j*p] > d+j) {
                    st.erase(mp(dist[u-j*p], u-j*p));
                    dist[u-j*p] = d+j;
                    st.insert(mp(d+j, u-j*p));
                }
                cnt++;
                assert(cnt < 1000*1000);
                if (doge[u-j*p].find(p) != doge[u-j*p].end()) break;
            }
        }
    }
    // cout << -1 << '\n';
}

int32_t main() {
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    cin >> n >> m;
    for (int i = 0; i < m; i++) {
        int a, b; cin >> a >> b;
        doge[a].insert(b);
        if (i == 0) s = a;
        if (i == 1) t = a;
    }
    dij(s);
    cout << (dist[t] == inf ? -1 : dist[t]) << '\n';
    // int sum = 0, i;
    // for ( i = 1; sum <= maxn; i++) sum += i;
    // cout << i << '\n';
    // sum = 0;
    // for (int j = 1; j <= i; j++) sum += maxn/j;
    // cout << sum << '\n';
    return 0;
}

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