program to check undirected graph is bipartite or not in c++

code/graph_algorithms/src/Bipartite_check/bipartite.cpp

@@ -0,0 +1,47 @@
+#include <iostream>
+#include <vector>
+#include <queue>
+int main()
+{
+    long int vertex , edge , u , v , c ;
+    bool flag=false;
+    // taking n ->number of vertex  and m -> number of edges
+    std::cin >> vertex >> edge;
+    // adj is 2-D vector to store edges between vertex
+    std::vector < std::vector < long int > > adj(vertex , std::vector <long int> ());
+    // color is use to store color of vertex
+    std::vector <long int> color(vertex , -1);
+    std::queue <long int> q;
+    //for number of edges times
+    for(int i=0;i < edge; ++i)
+    {
+        std::cin >> u >> v;
+        adj[u-1].push_back(v-1);
+        adj[v-1].push_back(u-1);
+    }
+    u=0;
+    color[u]=0;
+    q.push(u);
+    while(!q.empty())
+    {
+        c=q.front();
+        q.pop();
+        for(auto i=adj[c].begin();i!=adj[c].end(); ++i)
+        {
+            // updating color of vertex
+            if(color[*i]==-1 )
+            {
+                q.push(*i);
+                color[*i]=1-color[c];
+            }
+            else if(color[*i]==color[c])  // checking for bipartite graph
+            {
+                flag=true;
+            }
+        }
+    }
+    if( !flag )
+        std::cout << "Graph is bipartite" << "\n" ;
+    else
+        std::cout << "Graph is not bipartite" << "\n" ;
+}