Submission #695176

#	Time	Username	Problem	Language	Result	Execution time	Memory
695176		HossamHero7	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	36 / 100	1106 ms	243932 KiB

skyscraper

#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
#define endl '\n'
void solve(){
    int n,m;
    cin>>n>>m;
    vector<vector<int>> adj(n+1);
    vector<pair<int,int>> v(m);
    int pos = 0;
    for(int i=0;i<m;i++){
        int a,b;cin>>a>>b;
        v[i].first = a;
        v[i].second = b;
        if(i == 1) pos = a;
        adj[a].push_back(i);
    }
    queue<array<int,2>> q;
    vector<vector<bool>> vis(n,vector<bool>(m));
    q.push({v[0].first,0});
    vector<vector<int>> dis(n,vector<int>(m,0));
    while(q.size()){
        array<int,2> cur = q.front();     q.pop();
        for(auto ch : adj[cur[0]]){
            int p = v[ch].second;
            if(cur[0]+p<n && !vis[cur[0]+p][ch]){
                q.push({cur[0]+p,ch});
                dis[cur[0]+p][ch] = dis[cur[0]][cur[1]] + 1;
                vis[cur[0]+p][ch] = 1;
            }
            if(cur[0]-p>=0 && !vis[cur[0]-p][ch]){
                q.push({cur[0]-p,ch});
                dis[cur[0]-p][ch] = dis[cur[0]][cur[1]] + 1;
                vis[cur[0]-p][ch] = 1;
            }
        }

        int p = v[cur[1]].second;
        if(cur[0]+p<n && !vis[cur[0]+p][cur[1]]){
            q.push({cur[0]+p,cur[1]});
            dis[cur[0]+p][cur[1]] = dis[cur[0]][cur[1]] + 1;
            vis[cur[0]+p][cur[1]] = 1;
        }
        if(cur[0]-p>=0 && !vis[cur[0]-p][cur[1]]){
            q.push({cur[0]-p,cur[1]});
            dis[cur[0]-p][cur[1]] = dis[cur[0]][cur[1]] + 1;
            vis[cur[0]-p][cur[1]] = 1;
        }
    }
    if(v[0].first == v[1].first){
        cout<<0<<endl;
    }
    else {
        int ans = 1e9;
        for(int i=0;i<m;i++){
            if(i == 1) continue;
            if(dis[v[1].first][i] == 0) continue;
            ans = min(ans,dis[v[1].first][i]);
        }
        cout<<(ans==1e9?-1:ans)<<endl;
    }
}
int main()
{
    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 solve()':
skyscraper.cpp:11:9: warning: variable 'pos' set but not used [-Wunused-but-set-variable]
   11 |     int pos = 0;
      |         ^~~

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