Method DSU

MinimumCostWalkInWeightedGraph.java:4–10

(int n)

    int rank[];
    int parent[];
    DSU(int n){
        rank = new int[n];  //0
        parent = new int[n];
        for(int i=0;i<n;i++){
            parent[i] = i;
        }
    }
    public int find(int node){
        if(node == parent[node]){
            return node;