71 lines
1.9 KiB
Java
71 lines
1.9 KiB
Java
package DynamicProgramming;
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import java.util.LinkedList;
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import java.util.Queue;
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import java.util.Vector;
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public class FordFulkerson {
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static final int INF = 987654321;
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// edges
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static int V;
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static int[][] capacity, flow;
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public static void main(String[] args) {
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System.out.println("V : 6");
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V = 6;
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capacity = new int[V][V];
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capacity[0][1] = 12;
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capacity[0][3] = 13;
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capacity[1][2] = 10;
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capacity[2][3] = 13;
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capacity[2][4] = 3;
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capacity[2][5] = 15;
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capacity[3][2] = 7;
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capacity[3][4] = 15;
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capacity[4][5] = 17;
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System.out.println("Max capacity in networkFlow : " + networkFlow(0, 5));
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}
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private static int networkFlow(int source, int sink) {
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flow = new int[V][V];
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int totalFlow = 0;
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while (true) {
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Vector<Integer> parent = new Vector<>(V);
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for (int i = 0; i < V; i++) parent.add(-1);
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Queue<Integer> q = new LinkedList<>();
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parent.set(source, source);
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q.add(source);
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while (!q.isEmpty() && parent.get(sink) == -1) {
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int here = q.peek();
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q.poll();
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for (int there = 0; there < V; ++there)
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if (capacity[here][there] - flow[here][there] > 0 && parent.get(there) == -1) {
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q.add(there);
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parent.set(there, here);
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}
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}
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if (parent.get(sink) == -1) break;
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int amount = INF;
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String printer = "path : ";
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StringBuilder sb = new StringBuilder();
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for (int p = sink; p != source; p = parent.get(p)) {
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amount = Math.min(capacity[parent.get(p)][p] - flow[parent.get(p)][p], amount);
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sb.append(p + "-");
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}
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sb.append(source);
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for (int p = sink; p != source; p = parent.get(p)) {
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flow[parent.get(p)][p] += amount;
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flow[p][parent.get(p)] -= amount;
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}
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totalFlow += amount;
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printer += sb.reverse() + " / max flow : " + totalFlow;
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System.out.println(printer);
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}
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return totalFlow;
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}
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}
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