????

Author: raymo

dining.java

@@ -0,0 +1,115 @@
+import java.io.*;
+import java.util.*;
+public class dining {
+	public static final int NO_PARENT = -1; // Constant for no parent 
+	public static void main(String[] args) throws IOException {
+		BufferedReader f = new BufferedReader(new FileReader("dining.in"));
+		StringTokenizer st = new StringTokenizer(f.readLine());
+		int N,M,K;
+		N = Integer.parseInt(st.nextToken());
+		M = Integer.parseInt(st.nextToken());
+		K = Integer.parseInt(st.nextToken());
+		final int numOfCows =  N - 1;
+		List<List<Integer>> graph = new ArrayList<>(N);
+		for(int i = 0; i < N; i ++) {
+			graph.add(new ArrayList<>());
+		}
+		Map<Pair,Integer> cost = new HashMap<>(); 
+		for(int i =0 ; i < M; i ++) {
+			st = new StringTokenizer(f.readLine());
+			int start = Integer.parseInt(st.nextToken());
+			int end = Integer.parseInt(st.nextToken());
+			int edgeCost = Integer.parseInt(st.nextToken());
+			graph.get(start-1).add(end-1);
+			graph.get(end-1).add(start-1);
+			cost.put(new Pair(start-1,end-1), edgeCost);
+		}
+		Map<Pair,Integer> costWithHaybales = new HashMap<>(cost); 
+		System.out.println("Cost without haybales: "+cost);
+		System.out.println("Graph as an edgelist:  "+graph);
+		//int[] taste = new int[N];
+		Pair key;
+		//cost.get(new Pair(0,1));
+		for(int i = 0; i < K; i ++) {
+			st = new StringTokenizer(f.readLine());
+			int index = Integer.parseInt(st.nextToken()) - 1;
+			int value = Integer.parseInt(st.nextToken());
+			//costWithHaybales.get(new Pair(0,1));
+			for(int node: graph.get(index)) {
+				key = new Pair(index,node);//assert key.equals(new Pair(node,index));
+				//System.out.println("Map: "+costWithHaybales);
+				//System.out.println(key+ " "+costWithHaybales.get(key));
+				costWithHaybales.put(key, 
+						costWithHaybales.get(key) - value);
+			}
+			//taste[index] = value;
+		}
+		System.out.println("Cost with haybales:    "+costWithHaybales);
+		f.close();
+		int[] empty = new int[M];
+		Arrays.fill(empty, Integer.MAX_VALUE);
+		int[] distTo = new int[M];
+		for(int i = 0; i < numOfCows; i ++) {
+			distTo = Arrays.copyOf(empty, M);
+		}
+	}
+
+}
+
+// Order does not matter pair
+class Pair{
+	int x,y;
+	public Pair(int x,int y) {
+		this.x =x;
+		this.y =y;
+	}
+	@Override
+	public String toString() {
+		return "("+this.x+","+this.y+")";
+	}
+	@Override
+	public boolean equals(Object obj) {
+		if(obj instanceof Pair) {
+			Pair p = (Pair) obj;
+			if((p.x == this.x && p.y == this.y) || (p.x == this.y && this.x == p.y)) {
+				return true;
+			}
+		}else {
+			return false;
+		}
+		return false;
+	}
+	@Override
+	public int hashCode(){
+		return (Integer.hashCode(this.x) + 3) * (Integer.hashCode(this.y) + 3);
+	}
+}
+class Edge{
+	int x;
+	int y;
+	int weight;
+	public Edge(int x,int y,int weight) {
+		this.x = x;
+		this.y =y;
+		this.weight = weight;
+	}
+	public String toString() {
+		return "("+this.x+"--"+this.y+" = "+this.weight+")";
+	}
+	@Override
+	public boolean equals(Object obj) {
+		if(obj instanceof Edge) {
+			Edge other = (Edge) obj;
+			if((this.x == other.x && this.y == other.y) || (this.x == other.y && this.y == other.x)) {
+				if(this.weight == other.weight) {
+					return true;
+				}else {
+					return false;
+				}
+			}
+			return false;
+		}else {
+			return false;
+		}
+	}
+}