DiscreteMath/Fleurey at master · BeosDev/DiscreteMath · GitHub

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import java.util.LinkedList;
import java.util.Queue;
import java.util.Scanner;

/**
 * Created by linh on 17/09/2017.
 * Kiem tra tu canh x co di duoc toi y khong va neu xoa canh x va y
 * do thi co tang so thanh phan lien thong (cau) hay khong
 */
public class Fleurey {
    int numberOfVertex;
    int numberOfEdge;
    int edge[][];
    boolean isAlone[];

    boolean visited[];

    void input() {
        Scanner scanner = new Scanner(System.in);
        numberOfVertex = scanner.nextInt();
        numberOfEdge = scanner.nextInt();
        edge = new int[numberOfVertex + 1][numberOfVertex + 1];
        isAlone = new boolean[numberOfVertex+1];
        for (int i = 1; i <= numberOfEdge; i++) {
            int x = scanner.nextInt();
            int y = scanner.nextInt();
            edge[x][y] = edge[y][x] = scanner.nextInt();
        }
    }

    boolean checkIsAlone(int v){
        boolean check = true;
        for (int i = 1;i<=numberOfVertex;i++)
            if (edge[v][i] != 0){
                check = false;
                break;
            }
        return check;
    }
    void findPath(int startVertex) {
        Queue<Integer> queue = new LinkedList<>();
        queue.add(startVertex);
        int tempVertex = startVertex;
        while (!queue.isEmpty()) {
            boolean isPrint = true;
            for (int i = 1; i <= numberOfVertex; i++) {
         //       System.out.println(edge[tempVertex][i] != 0 && !isBridge(tempVertex, i));
                if (edge[tempVertex][i] != 0 && !isBridge(tempVertex, i)) {
                    edge[tempVertex][i]--;
                    edge[i][tempVertex]--;
        //            System.out.println(tempVertex+" "+isAlone[tempVertex]);
                    tempVertex = i;
                    isPrint = false;
                    queue.add(i);
                    break;
                }
            }
            if (isPrint){
                System.out.print(queue.remove()+" ");
            }
        }
    }
    int countLT(){
        int count = 0;
        visited = new boolean[numberOfVertex+1];
        for (int i = 1; i <= numberOfVertex; i++)
            if (!visited[i]) {
                dfs(i);
                count++;
            }
            return count;
    }
    private boolean isBridge(int x, int y) {
        visited = new boolean[numberOfVertex + 1];
        int count = 1;
        edge[x][y]--;
        edge[y][x]--;
        isAlone[x] = checkIsAlone(x);
        dfs(y);
        for (int i = 1; i <= numberOfVertex; i++)
            if (!isAlone[i] && !visited[i]) {
                dfs(i);
                count++;
            }
 //       System.out.println(count);
        edge[x][y]++;
        edge[y][x]++;
        return count > 1;
    }

    void dfs(int v) {
        visited[v] = true;
        for (int i = 1; i <= numberOfVertex; i++)
            if (!isAlone[i] && edge[v][i] != 0 && !visited[i]) {
                dfs(i);
            }
    }

    public static void main(String[] args) {
        Fleurey fleurey = new Fleurey();
        fleurey.input();
      /*  fleurey.edge[1][2]--;
        fleurey.edge[2][1]--;
        System.out.println(fleurey.countLT());*/
        fleurey.findPath(1);
    }

}