Create 2019-E-A.cpp

Author: tmp-coder

Diff for: kick-start/2019-E-A.cpp

@@ -0,0 +1,71 @@
+#include<bits/stdc++.h>
+
+using namespace std;
+
+#define ms(x,v) memset(x,(v), sizeof(x))
+#define msn(x,v,n) memset(x,(v),sizeof(x[0]) * n)
+#define INF 0x3f3f3f3f
+
+typedef long long LL;
+typedef pair<int,int> PII;
+
+const int MAXN = 1e5+10;
+
+int par[MAXN];
+
+int FIND(int x){
+    return x == par[x] ? x : par[x] = FIND(par[x]);
+}
+void UNOIN(int x,int y){
+    x = FIND(x);
+    y = FIND(y);
+    if(x !=y)
+        par[x] = par[y];
+}
+void solve(){
+    int n,m;
+    cin >> n >> m;
+    for(int i=1 ; i <=n ; ++i)
+        par[i] = i;
+    for(int i=0 ; i<m ; ++i){
+        int x,y;
+        cin >>x >> y;
+        UNOIN(x,y);
+    }
+    vector<vector<int> > G(n+1);
+    for(int i=1 ; i<=n ; ++i)
+        G[FIND(i)].push_back(i);
+    
+    int k=0;
+    int ans =0;
+    for(int i=1 ; i<=n ; ++i){
+        if(!G[i].empty()){
+            ans += G[i].size() -1;
+            k+=1;
+        }
+    }
+    ans += 2 * (k-1);
+    cout << " " << ans ;
+}
+
+int main(int argc, char const *argv[])
+{   
+    
+    ios :: sync_with_stdio(0);
+    cin.tie(0);
+    // cout.tie(0);
+    std::cout.precision(8);
+    std::cout.setf( std::ios::fixed, std:: ios::floatfield );
+    int T;
+    cin >> T;
+    
+    for(int kase =1;  kase <= T ; ++kase)
+    {   
+        cout << "Case #"<<kase << ":";
+
+        solve();
+        cout << '\n';
+    }
+
+    return 0;
+}