Submission #683920

#	Time	Username	Problem	Language	Result	Execution time	Memory
683920		speedyArda	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	57 / 100	1071 ms	2908 KiB

skyscraper

#include "bits/stdc++.h"
 
using namespace std;
const int MAXN = 3e4+5;
 
vector< vector < pair<int, int> > > adj(MAXN);
vector< vector <  int > > doges(MAXN);
int dp[MAXN];
//map< pair<int, int>, bool > done;
//map< pair<int, int>, int> max_road;
bool visited[MAXN];
int main() 
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int n, m;
    cin >> n >> m;
    int goal, begin;
    for(int i = 0; i < m; i++)
    {
        pair<int, int> temp;
        cin >> temp.first >> temp.second;
        if(i == 1)
            goal = temp.first;
        else if(i == 0)
            begin = temp.first;
        doges[temp.first].push_back(temp.second);
       
    }
 
    for(int i = 0; i <= n; i++) {
        dp[i] = 1e9;
        //visited[i] = false;
    }

    //visited[begin] = false;
    dp[begin] = 0;
    //set< pair<int, int> > curr; 
    //curr.insert({0, begin});
    int ans =  1e9;
    for(int i = 0; i < n; i++)
    {
        int v = -1;
        int max_road[n];
        for (int j = 0; j < n; j++) {
            max_road[j] = 0;
            if (!visited[j] && (v == -1 || dp[j] < dp[v]))
                v = j;
        }

         if (dp[v] == 1e9)
            break;

        visited[v] = true;
        for(int temp : doges[v]) {
            int currNode = v + temp;
            int cnt = 1;
            while(currNode < n)
            {
                int val = max_road[currNode];
                if(val == 0 || val > cnt)
                {
                    //adj[v].erase({val, currNode});
                    max_road[currNode] = cnt;
                    //adj[v].insert({cnt, currNode});
                    
                }
                //if(curr == 4)
                    //cout << temp.first << "\n";
                cnt++;
                currNode += temp;
            }

            currNode = v - temp;
            cnt = 1;
            while(currNode >= 0)
            {
                int val = max_road[currNode];
                if(val == 0 || val > cnt)
                {
                    //adj[v].erase({val, currNode});
                    max_road[currNode] = cnt;
                    //adj[v].insert({cnt, currNode});
                    
                }
                //if(curr == 4)
                    //cout << temp.first << "\n";
                cnt++;
                currNode -= temp;
            }

            
        }

        for(int to = 0; to < n; to++)
        {
            int len = max_road[to];
            if(len != 0)
            {
                if (dp[v] + len < dp[to]) {
                    dp[to] = dp[v] + len;
            }
            }
        }
        for (auto edge : adj[v]) {
            int to = edge.second;
            int len = edge.first;

            if (dp[v] + len < dp[to]) {
                dp[to] = dp[v] + len;
            }
        }

        //adj[v].clear();


    }
   
    ans = dp[goal];
    if(ans >= 1e9)
        ans = -1;
    cout << ans << "\n";
 
}

Compilation message (stderr)

skyscraper.cpp: In function 'int main()':
skyscraper.cpp:119:9: warning: 'goal' may be used uninitialized in this function [-Wmaybe-uninitialized]
  119 |     ans = dp[goal];
      |     ~~~~^~~~~~~~~~
skyscraper.cpp:37:15: warning: 'begin' may be used uninitialized in this function [-Wmaybe-uninitialized]
   37 |     dp[begin] = 0;
      |     ~~~~~~~~~~^~~

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