<?xml version="1.0"?>
<rss version="2.0">
   <channel>
      <title>HSG by Duc Anh Lai</title>
      <link>https://padlet.com/ducanhlai/Bookmarks</link>
      <description>Made with eyes on the prize</description>
      <language>en-us</language>
      <pubDate>2021-07-19 01:49:27 UTC</pubDate>
      <lastBuildDate>2025-03-27 08:57:11 UTC</lastBuildDate>
      <webMaster>hello@padlet.com</webMaster>
      <image>
         <url></url>
      </image>
      <item>
         <title>BT 1</title>
         <author>ducanhlai</author>
         <link>https://padlet.com/ducanhlai/Bookmarks/wish/3374461798</link>
         <description><![CDATA[]]></description>
         <enclosure url="https://padlet-uploads.storage.googleapis.com/1272530401/28f406263f31131f299e368a38ddd818/image.png" />
         <pubDate>2025-03-20 06:53:27 UTC</pubDate>
         <guid>https://padlet.com/ducanhlai/Bookmarks/wish/3374461798</guid>
      </item>
      <item>
         <title>BT2</title>
         <author>ducanhlai</author>
         <link>https://padlet.com/ducanhlai/Bookmarks/wish/3374463375</link>
         <description><![CDATA[]]></description>
         <enclosure url="https://padlet-uploads.storage.googleapis.com/1272530401/006002e82206a399aaece0072d4fb622/image.png" />
         <pubDate>2025-03-20 06:54:33 UTC</pubDate>
         <guid>https://padlet.com/ducanhlai/Bookmarks/wish/3374463375</guid>
      </item>
      <item>
         <title>BT 3</title>
         <author>ducanhlai</author>
         <link>https://padlet.com/ducanhlai/Bookmarks/wish/3374465599</link>
         <description><![CDATA[]]></description>
         <enclosure url="https://padlet-uploads.storage.googleapis.com/1272530401/a1b1e5bf1241fac95dbc68dba693aaff/image.png" />
         <pubDate>2025-03-20 06:56:01 UTC</pubDate>
         <guid>https://padlet.com/ducanhlai/Bookmarks/wish/3374465599</guid>
      </item>
      <item>
         <title></title>
         <author>ducanhlai</author>
         <link>https://padlet.com/ducanhlai/Bookmarks/wish/3374496807</link>
         <description><![CDATA[<p><a rel="noopener noreferrer nofollow" href="https://claoj.edu.vn/problem/hsg12_2023_v2_6">hsg12_2023_v2_6</a></p><p>#include &lt;bits/stdc++.h&gt; using namespace std; const int N = 9e4 + 5; const int M = 1e3 + 5; const int inf = 0x3f3f3f3f; int a[N],b[N],dist[M][M]; vector&lt;int&gt;g[M]; void bfs(int s) { queue&lt;int&gt;q; dist[s][s] = 1; q.push(s); while (!q.empty()) { int u = q.front(); q.pop(); for (auto v: g[u]) if (dist[s][v] == inf) { dist[s][v] = dist[s][u] + 1; q.push(v); } } } signed main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); freopen("friendship.inp","r",stdin); freopen("friendship.out","w",stdout); int n,s; cin &gt;&gt; n &gt;&gt; s; int maxi = 0; for (int i = 1; i &lt;= n; i++) { cin &gt;&gt; a[i] &gt;&gt; b[i]; a[i] = a[i] *<em> 2; b[i] = b[i] *</em> 2 + 1; maxi = max({maxi,a[i],b[i]}); g[a[i]].push_back(b[i]); g[b[i]].push_back(a[i]); } for (int i = 1; i &lt;= maxi; i++) { for (int j = 1; j &lt;= maxi; j++) dist[i][j] = inf; bfs(i); } int q; cin &gt;&gt; q; while (q--) { int x,y; cin &gt;&gt; x &gt;&gt; y; int ans = min({dist[a[x]][a[y]],dist[a[x]][b[y]],dist[b[x]][a[y]],dist[b[x]][b[y]]}); if (ans == inf) ans = -1; cout &lt;&lt; ans &lt;&lt; "\n"; } }</p><p><br/></p>]]></description>
         <enclosure url="https://padlet-uploads.storage.googleapis.com/1272530401/4d4739f0b3fcb97192b020892f5be408/hsg12_2023_v2_6.cpp" />
         <pubDate>2025-03-20 07:18:28 UTC</pubDate>
         <guid>https://padlet.com/ducanhlai/Bookmarks/wish/3374496807</guid>
      </item>
   </channel>
</rss>
