Added Connnect_components_using_DFS.cpp

Coding/C++/Connnect_components_using_DFS.cpp

@@ -0,0 +1,99 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+int n,m,k;
+const int N = 100;
+const int M = 100;
+int visited[N][M];
+char adj[N][M];
+
+
+
+void dfs(int i,int j,int &ans){
+
+    if((i>n-1 or j>m-1 or i<0 or j<0) ){
+        return;
+    }
+
+    if(adj[i][j]=='*'){
+        return;
+    }
+
+    visited[i][j]=1;
+    ans++;
+
+
+    for(int dx=-1;dx<=1;dx++){
+        for(int dy=-1;dy<=1;dy++){
+            if((abs(dx)+abs(dy))!=2){
+                if(visited[i+dx][j+dy]==0){
+                   dfs(i+dx,j+dy,ans);
+                }
+            }
+        }
+    }
+
+    if((i==n-1 or j==m-1 or i==0 or j==0) ){
+         if(adj[i][j]=='.'){
+            ans=0;
+         }
+    }
+
+}
+
+void solve(){
+    cin>>n>>m>>k;
+
+    for(int i=0;i<n;i++){
+        for(int j=0;j<m;j++){
+            cin>>adj[i][j];
+        }
+    } 
+
+    memset(visited,0,sizeof visited);
+
+    vector<pair<int,pair<int,int>>> ans;
+    int cnt =0;
+    for(int i=0;i<n;i++){
+        for(int j=0;j<m;j++){
+            if(adj[i][j]=='.' and visited[i][j]==0){
+               int x=0;
+               dfs(i,j,x);
+               ans[cnt].first=x;
+               ans[cnt].second.first = i;
+               ans[cnt].second.second = j;
+               cnt++;
+            }
+        }
+    } 
+
+
+    sort(ans.begin(),ans.end());
+    int res =0; 
+    for(int i=0;i<ans.size()-k;i++){
+         res+=ans[i].first;
+    }
+    cout<<res<<"\n";
+
+
+
+}
+
+int  main()
+{
+    ios_base::sync_with_stdio(false);
+    cin.tie(NULL);
+
+    #ifndef ONLINE_JUDGE
+        freopen("input.txt","r",stdin);
+        freopen("output.txt","w",stdout);
+    #endif
+
+    long long t=1;
+    // cin>>t;
+    while(t--){
+        solve();
+    }
+    return 0;
+
+}