Submission #1258865

#	Time	Username	Problem	Language	Result	Execution time	Memory
1258865		khanhdangiuu	Jakarta Skyscrapers (APIO15_skyscraper)	C++20	57 / 100	192 ms	158676 KiB

skyscraper

#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
#define ll long long
#define pi 3.14159265358979323846 
#define pb push_back
#define ar array

template<typename T, typename cmp = std::greater<T>>
using pq = priority_queue<T, vector<T>, cmp>;

template<typename T, typename cmp = std::less<T>>
using ordered_set = tree<T, __gnu_pbds::null_type, cmp, __gnu_pbds::rb_tree_tag, __gnu_pbds::tree_order_statistics_node_update>;

void chay()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    #define task "Hi"
    freopen(task".INP", "r", stdin);
    freopen(task".OUT", "w", stdout);
}

const int N = 30000, INF = numeric_limits<int>::max();
const int block = 70;
const long long INFLL = numeric_limits<ll>::max();
long long M = 1e9+7;

int n, m, B[N+5], P[N+5];
int cs[block+5][N+5];
vector<ar<int,2>> adj[block*N+5];

template<typename data = ll, typename datacanh = ar<int,2>>
vector<data> dijikstra(int u, int n, vector<datacanh> adj[])
{
    vector<bool> vis(n+1,false);
    vector<data> d(n+1, numeric_limits<data>::max());
    pq<ar<data,2>> q;
    q.push({0,u});
    d[u] = 0;
    while (!q.empty())
    {
        int u = q.top()[1]; q.pop();
        if (vis[u]) continue;
        vis[u] = true;
        for (datacanh canh : adj[u])
        {
            int v = canh[0];
            data w = canh[1];
            if (d[v] > d[u] + w)
            {
                d[v] = d[u] + w;
                q.push({d[v],v});
            }
        }   
    }
    return d;
}



void solve()
{
    cin>>n>>m;
    for (int i = 1; i <= m; i++)
    {
        cin>>B[i]>>P[i];
        B[i]++;
    }
    int dem = 0;
    for (int i = 0; i <= block; i++)
    {
        for (int j = 1; j <= n; j++)
        {
            cs[i][j] = ++dem;
        }
    }

    for (int i = 1; i <= block; i++)
    {
        for (int j = 1; j <= n; j++)
        {
            adj[cs[i][j]].pb({cs[0][j], 0});
            if (j - i >= 1) adj[cs[i][j]].pb({cs[i][j-i], 1});
            if (j + i <= n) adj[cs[i][j]].pb({cs[i][j+i], 1});
        }
    }

    for (int i = 1; i <= m; i++)
    {
        int ht = B[i], kc = P[i];
        if (kc > block)
        {
            for (int vitri = ht % kc; vitri <= n; vitri += kc)
            {
                adj[cs[0][ht]].pb({cs[0][vitri], abs(vitri - ht) / kc});
            }
        }
        else adj[cs[0][ht]].pb({cs[kc][ht], 0});
    }

    vector<int> d = dijikstra<int, ar<int,2>>(B[1], dem, adj);
    if (d[B[2]] != INF) cout<<d[B[2]];
    else cout<<-1;
}
 
signed main ()
{
    //chay();
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int t = 1;   
    //cin>>t; 
    while (t--)
    {
        solve();
    }

    return 0;
}

Compilation message (stderr)

skyscraper.cpp: In function 'void chay()':
skyscraper.cpp:23:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   23 |     freopen(task".INP", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
skyscraper.cpp:24:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   24 |     freopen(task".OUT", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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