Oct 12, 2010
A graph consists of vertices and edges that connect vertices. Write a program that reads a graph from a file and displays it on a panel. The first line in the file contains a number that indicates the number of vertices (n). The vertices are labeled as 0, 1, ..., n-1. Each subsequent line, with the format u x y v1, v2, ..., describes that the vertex u is located at position (x, y) with edges (u, v1), (u, v2), etc. Your program prompts the user to enter the name of the file, reads data from the file, and displays the graph on a panel.
Example File:
6
0 30 30 1 2
1 90 30 0 3
2 30 90 0 3 4
3 90 90 1 2 4 5
4 30 150 2 3 5
5 90 150 3 4
Analysis:
A graph is a mathematical structure with vertices and edges that connect the vertices. A graph is a very useful tool for modeling real-world problems. This project is to display the graph. The information for the graph is stored in a file. The number of the vertices n is stored in the first line of the file. The vertices are labeled 0, 1, 2, ..., n-1. The format of each subsequent line is u x y v1, v2, ..., which describes vertex u at location (x, y) and u is connected to vertices v1, v2, etc.
Design:
The program should first read the information about the graph from a file. The program prompts the user to enter the file name and read vertices location information into a two-dimensional array named position, where (position[0][0], position[0][1]) is the x- and y-coordinates for vertex 0. For example, in the sample graph, (position[0][0], position[0][1]) is (30, 30). The program reads the edge information into an array of ArrayList named edge (ArrayList is covered in Chapter 11). For example, in the sample graph, edge[0].Is an ArrayList that contains elements 1 and 2, which indicates that vertex 0 is connected to vertex 1 and vertex 2. position and edge should be created as followed:
int[][] position = new int[n][2];
ArrayList[] edge = new ArrayList[n];
I don't know how to implement the code. I have started but I am not sure how to proceed.
import java.awt.Graphics;
import java.util.*;
import java.io.*;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Exercise15_27 extends JFrame {
[code]....
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Apr 22, 2015
The thing my coding for sudoku is not working for few inputs... it works fine with all its value initially at 0, but when i place numbers more than 4 at random places it stops responding (it doesn't show any value). My assignment is to get a solved sudoku for these values:
//Sample Input:
{0,2,7,3,8,0,0,1,0},
{0,1,0,0,0,6,7,3,5},
{0,0,0,0,0,0,0,2,9},
{3,0,5,6,9,2,0,8,0},
{0,0,0,0,0,0,0,0,0},
{0,6,0,1,7,4,5,0,3},
{6,4,0,0,0,0,0,0,0},
{9,5,1,8,0,0,0,7,0},
{0,8,0,0,6,5,3,4,0}
My current code
public class Sudoku {
static int userGrid[][]=new int[][]
{{0,0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0,0}};//[horizontal][vertical]
static int grid[][]=new int[9][9];//the grid that the program experiments on
[Code] .....
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Oct 29, 2014
I'm writing a program that accepts three doubles from the user, and performs calculations on them. I want to be able to handle input mismatch exceptions on each individually (i.e., if the user enters a double for the first, then a letter for the second, I'd like to be able to keep the value entered for the first, and only require that the user try again with the second, then the third, etc.)... I tried putting each input instance into its own try/catch blocks, but it always goes back to #1 when an invalid input is entered. Right now, I have all three in one try/catch:
Java Code:
package com.itse2317;
import java.util.Scanner;
import java.util.InputMismatchException;
class Triangle
{
public static double side1 = 0.0, side2 = 0.0, side3 = 0.0;
[code]...
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