Create 1676-Road Construction.cpp

DSU

Author: manitajay

cses graph/1676-Road Construction.cpp

@@ -0,0 +1,94 @@
+// JAI BAJARANG BALI
+
+// manitianajay45
+
+// give me some sunshine, give me some rain , give me another chance to grow up once again....
+
+// sab moh maya hai....
+
+
+// DSU
+
+
+#include <bits/stdc++.h>
+using namespace std;
+
+#define ll long long
+#define mod 1000000007
+ll n,m;
+
+vector<ll> fn(200005,0);
+vector<ll> cnt(2000005,0);
+
+vector<ll> vec[200005];
+
+
+ll mx;
+ll sz=1;
+
+
+void unite(ll u,ll v){
+    // cout<<u<<" st"<<v<<endl;
+    u=fn[u];
+    v=fn[v];
+    // cout<<u<<" "<<v<<endl;
+
+    if(u!=v){
+    if(cnt[u]!=0 && cnt[v]!=0){
+        mx--;
+    }
+    if(cnt[u]<=cnt[v]){
+        cnt[v]+=cnt[u];
+        cnt[u]=0;
+        sz=max(sz,cnt[v]);
+
+        for(auto i:vec[u]){
+            fn[i]=v;
+            vec[v].push_back(i);
+        }
+    }else{
+        cnt[u]+=cnt[v];
+        cnt[v]=0;
+        sz=max(sz,cnt[u]);
+
+        for(auto i:vec[v]){
+            fn[i]=u;
+            vec[u].push_back(i);
+        }
+    }
+    }
+}
+
+
+
+
+
+
+int main()
+{
+    ios_base::sync_with_stdio(false);
+    cin.tie(NULL);
+
+    // ll n;
+    cin >> n>>m;
+
+    for(ll i=1;i<=n;i++){
+        fn[i]=i;
+        cnt[i]=1;
+        vec[i].push_back(i);
+    }
+    // cout<<mx<<endl;
+    mx=n;
+
+    for (ll i = 0; i <m; i++)
+    {
+        ll u,v;
+        cin>>u>>v;
+        // mx--;
+        unite(u,v);
+        cout<<mx<<" "<<sz<<endl;
+
+    }    
+
+    return 0;
+}