Submission #142786

#	Time	Username	Problem	Language	Result	Execution time	Memory
142786		12tqian	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	100 / 100	240 ms	72380 KiB

skyscraper

#pragma comment(linker, "/stack:200000000")
//#pragma GCC optimize("Ofast")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#pragma GCC optimize ("O3")
#pragma GCC target ("sse4")
#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>

using namespace std;
using namespace __gnu_pbds;
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;

const double PI = 4 * atan(1);

#define sz(x) (int)(x).size()
#define ll long long
#define ld long double
#define mp make_pair
#define pb push_back
#define eb emplace_back
#define pii pair <int, int>
#define vi vector<int>
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()
#define vpi vector<pair<int, int>>
#define vpd vector<pair<double, double>>
#define pd pair<double, double>

#define f0r(i,a) for(int i=0;i<a;i++)
#define f1r(i,a,b) for(int i=a;i<b;i++)
#define trav(a, x) for (auto& a : x)

void fast_io(){
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);
}
void io(string taskname){
    string fin = taskname + ".in";
    string fout = taskname + ".out";
    const char* FIN = fin.c_str();
    const char* FOUT = fout.c_str();
    freopen(FIN, "r", stdin);
    freopen(FOUT, "w", stdout);
    fast_io();
}
const int MAX = 3e4 + 5;
const int INF = 1e9;

int n, m;
map<int, map<int, vi>> um;
///first is the modulus
///next is remainders, then is set of doges that works
vpi d;
vpi adj[MAX];
set<int> power[MAX];



int dist[MAX];
int par[MAX];
int dijkstra(int st, int end) {
    fill(dist, dist + MAX, INF);

    dist[st] = 0;

    // <distance, <previous vertex, current vertex>>
    priority_queue<pair<ll, pair<int, int>>, vector<pair<ll, pair<int, int>> >, greater<pair<ll, pair<int ,int>> > > pq;
    pq.emplace(0, make_pair(st, st));

    while(!pq.empty()){
        auto top = pq.top();
        pq.pop();

        ll d = top.first;
        int prev = top.second.first;
        int cur = top.second.second;

        if(d > dist[cur])
            continue;

        par[cur] = prev;

        for(auto v: adj[cur]){
            int nxt = v.first;
            ll w = v.second;
            if (dist[nxt] > dist[cur] + w) {
                dist[nxt] = dist[cur] + w;
                pq.emplace(dist[nxt], make_pair(cur, nxt));
            }
        }
    }
    return dist[end];
}
int main(){
    fast_io();
    cin >> n >> m;
    f0r(i, m){
        int bi, pi;
        cin >> bi >> pi;
        d.eb(mp(bi, pi));
        power[bi].insert(pi);
    }
    f0r(i, n){
        for(int p: power[i]){
            int cur = i+p;
            int val = 1;
            while(cur<n){
                adj[i].eb(mp(cur, val));
                if(power[cur].find(p) != power[cur].end()) break;
                val++;
                cur += p;
            }
            cur = i-p;
            val = 1;
            while(cur>=0){
                adj[i].eb(mp(cur, val));
                if(power[cur].find(p) != power[cur].end()) break;
                val++;
                cur -= p;
            }
        }
    }
    int res = dijkstra(d[0].f, d[1].f);
    if(res == INF) cout << -1 << endl;
    else cout << res << endl;

    return 0;
}

Compilation message (stderr)

skyscraper.cpp:1:0: warning: ignoring #pragma comment  [-Wunknown-pragmas]
 #pragma comment(linker, "/stack:200000000")
 
skyscraper.cpp: In function 'void io(std::__cxx11::string)':
skyscraper.cpp:47:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     freopen(FIN, "r", stdin);
     ~~~~~~~^~~~~~~~~~~~~~~~~
skyscraper.cpp:48:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     freopen(FOUT, "w", stdout);
     ~~~~~~~^~~~~~~~~~~~~~~~~~~

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