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Check whether a given graph is Bipartite or not….FTC

A bipartite graph is a special kind of graph that consists of two vertex sets.

There is an undirected graph with n nodes, where each node is numbered between 0 and n - 1. You are given a 2D array graph, where graph[u] is an array of nodes that node u is adjacent to. More formally, for each v in graph[u], there is an undirected edge between node u and node v. The graph has the following properties:

  • There are no self-edges (graph[u] does not contain u).
  • There are no parallel edges (graph[u] does not contain duplicate values).
  • If v is in graph[u], then u is in graph[v] (the graph is undirected).
  • The graph may not be connected, meaning there may be two nodes u and v such that there is no path between them.

A graph is bipartite if the nodes can be partitioned into two independent sets A and B such that every edge in the graph connects a node in set A and a node in set B.

Return true if and only if it is bipartite.

Example 1:

Input: graph = [[1,2,3],[0,2],[0,1,3],[0,2]]
Output: false
Explanation: There is no way to partition the nodes into two independent sets such that every edge connects a node in one and a node in the other.

class BipartiteChecker:
    def Bipartite(self, graph) -> bool:
        glen = len(graph)
        s = []
        vis = [0] * glen
        for i in range(glen):
            if vis[i]: continue
            vis[i] = 1
            s.append(i)
            while len(s):
                curr = s.pop()
                edges = graph[curr]
                for next in edges:
                    if not vis[next]:
                        vis[next] = vis[curr] ^ 3
                        s.append(next)
                    elif vis[curr] == vis[next]:
                        return False
        return True



# Driver
G = BipartiteChecker()
'''
Matrx = [[1,2,3],[0,2],[0,1,3],[0,2]]
'''
Matrx=[]
while True:
    arr=list(map(str,input().split(" ")))
    if arr != ['']:
        Matrx.append(list(map(int,arr)))
    else:
        break

print("True") if G.Bipartite(Matrx) else print("False")


INPUT_1:
1  2  3
0  2
0  1  3
0  2

OUTPUT:
False


INPUT_2:
1  3
0  2
1  3
0  2

OUTPUT:
True


ILLUSTRATION

Executed using python3 Linux