Submission #738643

#	Time	Username	Problem	Language	Result	Execution time	Memory
738643		Alihan_8	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	100 / 100	170 ms	126108 KiB

skyscraper

#include <bits/stdc++.h>

using namespace std;

#define all(x) x.begin(), x.end()
#define pb push_back
#define ln '\n'
#define int long long

template <class _T>
bool chmin(_T &x, const _T &y){
    bool flag = false;
    if ( x > y ){
        x = y; flag |= true;
    }
    return flag;
}

template <class _T>
bool chmax(_T &x, const _T &y){
    bool flag = false;
    if ( x < y ){
        x = y; flag |= true;
    }
    return flag;
}

signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    int n, m; cin >> n >> m;
    set <int> s[n + 1];
    int st = -1, en = -1;
    for ( int i = 1; i <= m; i++ ){
        int pos, v; cin >> pos >> v;
        st = i == 1 ? pos : st;
        en = i == 2 ? pos : en;
        s[pos].insert(v);
    }
    vector <pair<int,int>> g[n];
    for ( int i = 0; i < n; i++ ){
        for ( auto d: s[i] ){
            for ( int j = i - d; j >= 0; j -= d ){
                g[i].pb({j, (i - j) / d});
                if ( s[j].count(d) ) break;
            }
            for ( int j = i + d; j < n; j += d ){
                g[i].pb({j, (j - i) / d});
                if ( s[j].count(d) ) break;
            }
        }
    }
    const int inf = 1e17 + 1;
    vector <int> dis(n, inf);
    dis[st] = 0;
    priority_queue <pair<int,int>> q;
    q.push({0, st});
    while ( !q.empty() ){
        auto [val, x] = q.top();
        q.pop(); val = -val;
        if ( val > dis[x] ) continue;
        for ( auto [to, w]: g[x] ){
            if ( chmin(dis[to], w + val) ){
                q.push({-dis[to], to});
            }
        }
    }
    int res = dis[en];
    cout << (res == inf ? -1 : res);

    cout << '\n';
}

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