Subset Component | HackerRank

You are given an array with -bit integers: .

BIT(x, i) = (x >> i) & 1, where is the lower bit of in binary form. If we regard every bit as a vertex of a graph G, there is an undirected edge between vertices and if there is a value such that BIT(d[k], i) == 1 && BIT(d[k], j) == 1.

For every subset of the input array, how many connected-components are there in that graph?

A connected component in a graph is a set of nodes which are accessible to each other via a path of edges. There may be multiple connected components in a graph.

Example

In the real challenge, there will be nodes associated with each integer in represented as a bit binary value. For clarity, only bits will be shown in the example but all will be considered in the calculations.

    Decimal  Binary Edges   Node ends
    d[0] = 1   0001   0
    d[1] = 2   0010   0
    d[2] = 3   0011   1       0 and 1
    d[3] = 5   0101   1       0 and 2

Consider all subsets:

                 Edges
    Subset   Count  Nodes  Connected components
    {1}         0           64
    {2}         0           64
    {3}         1   0-1     63
    {5}         1   0-2     63
    {1,2}       0           64
    {1,3}       1   0-1     63
    {1,5}       1   0-2     63
    {2,3}       1   0-1     63
    {2,5}       1   0-2     63
    {3,5}       2   0-1-2   62
    {1,2,3}     1   0-1     63
    {1,2,5}     1   0-2     63
    {1,3,5}     2   0-1-2   62
    {2,3,5}     2   0-1-2   62
    {1,2,3,5}   2   0-1-2   62
    Sum                    944

The values and have bits set, so they have edge each. If a subset contains only a or , there will be one connected component with nodes, and components with node for a total of .

If both and are in a subset, component with nodes and is formed since node is one end of each edge described. The other nodes are solitary, so there are connected components total.

All other values have only bit set, so they have no edges. They have components with node each.

Function Description

Complete the findConnectedComponents function in the editor below.

findConnectedComponents has the following parameters:

int d[n]: an array of integers

Returns

int: the sum of the number of connected components for all subsets of

Input Format

The first row contains the integer , the size of .
The next row has space-separated integers, .

Constraints

Sample Input 1

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3
2 5 9

Sample Output 1

Explanation 1

There are subset of .

{}
=> We don't have any number in this subset => no edge in the graph => Every node is a component by itself => Number of connected-components = 64.

{2}
=> The Binary Representation of 2 is . There is a bit at only one position. => So there is no edge in the graph, every node is a connected-component by itself => Number of connected-components = 64.

{5}
=> The Binary Representation of 5 is . There is a bit at the 0^th and 2^nd position. => So there is an edge: (0, 2) in the graph => There is one component with a pair of nodes (0,2) in the graph. Apart from that, all remaining 62 vertices are indepenent components of one node each (1,3,4,5,6...63) => Number of connected-components = 63.

{9}
=> The Binary Representation of 9 is . => There is a 1-bit at the 0^th and 3^rd position in this binary representation. => edge: (0, 3) in the graph => Number of components = 63

{2, 5}
=> This will contain the edge (0, 2) in the graph which will form one component
=> Other nodes are all independent components
=> Number of connected-component = 63

{2, 9}
=> This has edge (0,3) in the graph
=> Similar to examples above, this has 63 connected components

{5, 9}
=> This has edges (0, 2) and (0, 3) in the graph
=> Similar to examples above, this has 62 connected components

{2, 5, 9}
=> This has edges(0, 2) (0, 3) in the graph. All three vertices (0,2,3) make one component => Other 61 vertices are all independent components
=> Number of connected-components = 62