Question

Is there anyway to solve below problem in Java?

Wherever there is int it gives an error! It's not only line 20! it give an runtime error everywhere get int after string! or even before read string!

cities[i] = sc.next(); //This way does not work!!!!

==============

input

San Francisco
Las Vegas
8
San Diego
Los Angeles
San Francisco
San Jose
Sacramento
Santa Barbara
Las Vegas
Pheonix
8 19
0 1
0 3
1 0
1 2
1 4
1 3
2 1
2 5
2 6
2 7
3 7
3 0
3 1
4 7
4 1
5 2
6 2
7 2
7 3

==============

Error:

==============

Exception in thread "main" java.util.InputMismatchException
        at java.util.Scanner.throwFor(Scanner.java:864)
        at java.util.Scanner.next(Scanner.java:1485)
        at java.util.Scanner.nextInt(Scanner.java:2117)
        at java.util.Scanner.nextInt(Scanner.java:2076)
        at Solution.main(myFuncs.java:20)

=======================

==============

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

public class myFuncs{

    public static void main(String arg[]) {
        Scanner sc = new Scanner(System.in);
        String s1, s2;
        s1 = sc.nextLine(); //first city
        s2 = sc.nextLine(); //second city
        int n = sc.nextInt(); //total number of cities
        String cities[] = new String[n];
        for (int i = 0; i < n; i++) {
            cities[i] = sc.nextLine(); //getting each city and storing them
        }
        n = sc.nextInt();
        int e = sc.nextInt();
        int adj[][] = new int[n][e];
        for (int i = 0; i < n; i++)
            for (int j = 0; j < e; j++)
                adj[i][j] = 0;
        for (int i = 0; i < e; i++) {
            int c1 = sc.nextInt();
            int c2 = sc.nextInt();
            adj[c1][c2] = 1;
            adj[c2][c1] = 1;
        }

        int index1 = -1, index2 = -1;

        for (int i = 0; i < n; i++) {
            if (cities[i].equals(s1)) index1 = i; //storing the index of first city
            if (cities[i].equals(s2)) index2 = i; //storing the index of second city
        }

        adj[index1][index2] = 0;
        adj[index2][index1] = 0;

        System.out.println(cities[index1] + " " + index1);
        System.out.println(cities[index2] + " " + index2);

        if (bfs(adj, index1, index2, n)) System.out.println("true");
        else System.out.println("false");
    }

    public static boolean bfs(int adj[][], int source, int dest, int V) {

        boolean visited[] = new boolean[V];

        LinkedList < Integer > queue = new LinkedList < Integer > ();

        visited[source] = true;
        //visited[dest]=true;
        queue.add(source);

        while (queue.size() != 0) {

            int s = queue.poll();

            if (queue.size() != 0)
                queue.remove();

            System.out.print(s + " ");

            for (int i = s; i < V; i++) {
                if (adj[s][i] == 1 && !visited[i]) {
                    visited[i] = true;
                    queue.add(i);
                    if (i == dest) return true;
                }
            }

        }

        return false;
    }

}

Answer 1

In case of any query, do comment. Please rate answer as well. Thanks

There are two ways:

First Way: Actually you are using int n = sc.nextInt() in line 15 and pressing enter so it is taking first item of cities array as blank. So either you press only space , it will work for you. So when you use nextInt() you have to just press space after that.

I have only provided the space after third input then your old program also worked. Please see the output.

Second way: or modify the line 20 and other lines where you are taking integer input as below, then if you press enter it will work for you:

int n = Integer.valueOf(sc.nextLine());

Output: