added BFS Using Queue

BFS Using Queue

C++/Data-Structures/Graph/BFS.cpp

@@ -0,0 +1,48 @@
+#include<bits/stdc++.h> 
+#include<ext/pb_ds/assoc_container.hpp>
+#include<ext/pb_ds/tree_policy.hpp>
+#pragma GCC optimize("Ofast")
+#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,fma")
+#pragma GCC optimize("unroll-loops")
+const unsigned int M = 1000000007;
+using namespace std;
+// Check
+using namespace __gnu_pbds;
+typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> T_set; // PBDS_set
+typedef tree<int,null_type,less_equal<int>,rb_tree_tag,tree_order_statistics_node_update> T_multiset; // PBDS_multiset
+
+void solve()
+{
+    int n ,m,u,v;
+    cin>>n>>m;
+    vector<list<int>> adj(n+1);
+    vector<bool> vis(n+1,false);
+    for(int i = 0; i < n ; i++ ){
+        cin>>u>>v;
+        adj[u].push_back(v);
+        adj[v].push_back(u);
+    }
+    queue<int> temp;
+    temp.push(1);
+    vis[1] = true;
+    while(!temp.empty()){
+        int curr = temp.front();
+        cout<<curr<<" ";
+        temp.pop();
+        for(int elem : adj[curr]){
+            if(!vis[elem]){
+                temp.push(elem);
+                vis[elem] = true;
+             }
+        }
+    }
+
+}
+int main()
+{
+ios_base::sync_with_stdio(false);
+cout.tie(NULL);
+cin.tie(NULL);
+solve();
+return 0;
+}