DZone Snippets: example code

DOM Parser Demo Code

sumit.tambekar (sumit tambekar) — Tue, 15 Apr 2008 18:04:06 GMT

//above class will search a movie/actor/producer name & will accordingly print other
//details
import javax.swing.text.html.parser.DocumentParser;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import java.util.*;
public class Movie_XML implements Movie
{

ArrayList movies = new ArrayList();

public ArrayList searchByActorName(String nm,String key)
{
try
{
DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder docBuilder = docFactory.newDocumentBuilder();
Document doc = docBuilder.parse("movie.xml");
NodeList nodeList = null;

if(key.equalsIgnoreCase("actor"))
nodeList = doc.getElementsByTagName("actor");
else if(key.equalsIgnoreCase("movie"))
nodeList = doc.getElementsByTagName("name");
else
nodeList = doc.getElementsByTagName("producer");

Node temp = null, parent=null;
NodeList childs = null;
for(int i=0;i {
temp = nodeList.item(i);
if(temp.getTextContent().equalsIgnoreCase(nm))
{
parent = temp.getParentNode();
childs = parent.getChildNodes();
MovieDB mDB = new MovieDB();
for(int j=0;j {
Node nd = childs.item(j);
if(nd.getNodeType() == Node.ELEMENT_NODE)
{
String name = nd.getNodeName();
//System.out.println(name);
if(name.equalsIgnoreCase("id"))
{
mDB.setId(nd.getTextContent());
}
if(name.equalsIgnoreCase("name"))
{
mDB.setName(nd.getTextContent());
}
if(name.equalsIgnoreCase("producer"))
{
mDB.setProducer(nd.getTextContent());
}
if(name.equalsIgnoreCase("director"))
{
mDB.setDirector(nd.getTextContent());
}
if(name.equalsIgnoreCase("music_director"))
{
mDB.setMusic_director(nd.getTextContent());
}
if(name.equalsIgnoreCase("actor"))
{
mDB.setActor(nd.getTextContent());
}
if(name.equalsIgnoreCase("actress"))
{
mDB.setActress(nd.getTextContent());
}
}
}
movies.add(mDB);
}
}
return movies;
}
catch(Exception e)
{
throw new CustomException("err in Searching by actor name",e);
}
}
}

//this class will call the above class by sending appropriate parmeters

import java.util.*;
import java.io.*;
public class XMLDemo
{
public static void main(String[] args)
{
try
{
InputStreamReader ir = new InputStreamReader(System.in);
BufferedReader br = new BufferedReader(ir);
while(true)
{
System.out.println("\n Enter the Choice : ");
System.out.println(" 1 : Search By Actor Name : ");
System.out.println(" 2 : Search By Movie Name : ");
System.out.println(" 3 : Search By Producer Name : ");
System.out.println(" 4 : Quit : ");
try
{
int ch = Integer.parseInt(br.readLine());
switch(ch)
{
case 1 :
System.out.println("Enter Actor Name : ");
String actorName = br.readLine();
search(actorName,"actor");
break;
case 2 :
System.out.println("Enter Movie Name");
String movieName = br.readLine();
search(movieName,"movie");
break;
case 3 :
System.out.println("Enter Producer Name");
String producerName = br.readLine();
search(producerName,"producer");
break;
case 4 :
System.out.println("Exiting");
System.exit(0);
default :
System.out.println("Invalid Choice !");
}
}
catch(Exception e)
{
System.out.println("Invalid Choice !");
}
}//end of while
}
catch(Exception e)
{
//e.printStackTrace();
throw new CustomException("err in main",e);
}
}

static void search(String name,String key)
{
try
{
ArrayList movies = new ArrayList();
Movie_XML obj = new Movie_XML();
movies = obj.searchByActorName(name,key);
int i =0;
System.out.println();
for(i=0;i {
MovieDB mDB = movies.get(i);
System.out.println("ID : "+mDB.getId());
System.out.println("Name : "+mDB.getName());
System.out.println("Producer : "+mDB.getProducer());
System.out.println("Director : "+mDB.getDirector());
System.out.println("Music : "+mDB.getMusic_director());
System.out.println("Actor : "+mDB.getActor());
System.out.println("Actress : "+mDB.getActress());
}
System.out.println(i+" Record Found!");
}
catch(Exception e)
{
throw new CustomException("err in byActor",e);
}
}
}

//this class will hold the details of the movie(id,name,---)

import java.util.*;
public class MovieDB
{
private String id,name,year;
private ArrayList actor,actress;
private String director,producer,music_director;

public MovieDB()
{
actor = new ArrayList();
actress = new ArrayList();
}

public void setId(String id)
{
this.id = id;
}

public void setName(String name)
{
this.name = name;
}

public void setYear(String year)
{
this.year = year;
}

public void setDirector(String director)
{
this.director = director;
}

public void setProducer(String producer)
{
this.producer = producer;
}

public void setMusic_director(String music_director)
{
this.music_director = music_director;
}

public void setActor(String actor)
{
this.actor.add(actor);
}

public void setActress(String actress)
{
this.actress.add(actress);
}

public String getId()
{
return id;
}

public String getName()
{
return name;
}

public String getProducer()
{
return producer;
}

public String getDirector()
{
return director;
}

public String getMusic_director()
{
return music_director;
}

public ArrayList getActor()
{
return actor;
}

public ArrayList getActress()
{
return actress;
}
}

//movie interface

import java.util.*;
public interface Movie
{
public ArrayList searchByActorName(String nm,String key);
}

DOM Parser Demo Code

sumit.tambekar (sumit tambekar) — Tue, 15 Apr 2008 18:03:51 GMT

dbg - debuging routine

uten (ksflock) — Sat, 20 Oct 2007 07:31:06 GMT

A handy little routine to debug autoit scripts



dbg("Log this message")

Func dbg($msg, $error=@error, $extended=@extended, $ScriptLineNumber=@ScriptLineNumber)

    Local $out = "(" & $ScriptLineNumber & ")(" & $error & ")(" & $extended & ") := " & $msg 

    ;Output to application attaching a console to the script engine

    ConsoleWrite($msg & @CRLF)

    ;Output to debugger (dbgview.exe)

    DllCall("kernel32.dll", "none", "OutputDebugString", "str", $out)

EndFunc

Generate combinations

scvalex (Alexandru Scvortov) — Wed, 17 Oct 2007 14:43:38 GMT

Code generates all the combinations of n elements choosing k elements.

See this for definition.

See this for explanation.



#include 



/* Prints out a combination like {1, 2} */

void printc(int comb[], int k) {

	printf("{");

	int i;

	for (i = 0; i < k; ++i)

		printf("%d, ", comb[i] + 1);

	printf("\b\b}\n");

}



/*

	next_comb(int comb[], int k, int n)

		Generates the next combination of n elements as k after comb



	comb => the previous combination ( use (0, 1, 2, ..., k) for first)

	k => the size of the subsets to generate

	n => the size of the original set



	Returns: 1 if a valid combination was found

		0, otherwise

*/

int next_comb(int comb[], int k, int n) {

	int i = k - 1;

	++comb[i];

	while ((i >= 0) && (comb[i] >= n - k + 1 + i)) {

		--i;

		++comb[i];

	}



	if (comb[0] > n - k) /* Combination (n-k, n-k+1, ..., n) reached */

		return 0; /* No more combinations can be generated */



	/* comb now looks like (..., x, n, n, n, ..., n).

	Turn it into (..., x, x + 1, x + 2, ...) */

	for (i = i + 1; i < k; ++i)

		comb[i] = comb[i - 1] + 1;



	return 1;

}



int main(int argc, char *argv[]) {

	int n = 5; /* The size of the set; for {1, 2, 3, 4} it's 4 */

	int k = 3; /* The size of the subsets; for {1, 2}, {1, 3}, ... it's 2 */

	int comb[16]; /* comb[i] is the index of the i-th element in the

			combination */



	/* Setup comb for the initial combination */

	int i;

	for (i = 0; i < k; ++i)

		comb[i] = i;



	/* Print the first combination */

	printc(comb, k);



	/* Generate and print all the other combinations */

	while (next_comb(comb, k, n))

		printc(comb, k);



	return 0;

}

Permutations

scvalex (Alexandru Scvortov) — Wed, 03 Oct 2007 10:00:09 GMT

Generates all permutation of n. Uses the naive (stupid) "let's generate all imaginable possibilities and see which are permutations" algorithm.

Time: O(n!)



#include 



int next(int v[], int n) {

	int i = n - 1;

	v[i] = v[i] + 1;

	while ((i >= 0) && (v[i] > n)) {

		v[i] = 1;

		i--;

		if(i >= 0)

			v[i]++;

	}



	if (i < 0)

		return 0;

	return 1;

}



void printv(int v[],int n) {

	int i;



	for (i = 0; i < n; i++)

		printf("%d", v[i]);

	printf("\n");

}



int is_perm(int v[], int n) {

	int i, j;



	for (i = 0; i < n; i++)

		for (j = i + 1; j < n; j++)

			if (v[i] == v[j])

				return 0;



	return 1;

}



int main(int argc, char *argv[]) {

	int v[128];

	int n = 6;

	int i;

	for(i = 0; i <= n; i++)

		v[i] = i + 1;



	while (next(v,n))

		if (is_perm(v,n))

			printv(v,n);



	return 0;

}

The Qeens Problem

scvalex (Alexandru Scvortov) — Tue, 02 Oct 2007 08:18:50 GMT

Prints all valid ways to arrange n qeens on a n x n chessboard so that the qeens don't attack each other.



#include 

#include 



typedef std::vector< int > Vect;

typedef std::vector< Vect > List;



const int n = 12;



bool checkRow(const Vect &v, int k) {

	for (int i = k - 1; i >= 0; --i)

		if (v[k] == v[i])

			return false;



	return true;

}



bool checkDiag(const Vect &v, int k) {

	for (int i = k - 1; i >= 0; --i)

		if (k - i == abs(v[k] - v[i]))

			return false;

	

	return true;

}



List filter(List l, int k) {

	List r;

	for (List::const_iterator it = l.begin(); it != l.end(); ++it) {

		if (checkRow(*it, k) && checkDiag(*it, k))

			r.push_back(*it);

	}

	

	return r;

}



List qeens(int k) {

	if (0 == k) {

		List l;

		l.push_back(Vect());

		return l;

	}

	

	List l = qeens(k - 1);

	List r;

	for (List::iterator it = l.begin(); it != l.end(); ++it) {

		for (int newRow = 1; newRow <= n; ++newRow) {

			Vect v(*it);

			v.push_back(newRow);

			r.push_back(v);

		}

	}

	

	r = filter(r, k - 1);

	

	return r;

}



void printS(List l) {

	for (List::const_iterator it = l.begin(); it != l.end(); ++it) {

		for (Vect::const_iterator jt = it->begin(); jt != it->end(); ++jt)

			std::cout << *jt << " ";

		std::cout << std::endl;

	}

}



int main(int argc, char *argv[]) {

	List l = qeens(n);

	

	printS(l);

	

	return 0;

}

Quicksort

scvalex (Alexandru Scvortov) — Mon, 01 Oct 2007 10:43:04 GMT

Qucksort written in C. Uses the Hoare partition algorithm.



typedef struct {

	int len;

	int elem[50240];

} vector;



void printv(char *str, vector v) {

	printf("%s", str);

	int i = 0;

	for (; i < v.len; ++i)

		printf("%d ", v.elem[i]);

	printf("\n");

}



#define MAX(a, b) ((a > b) ? (a) : (b))

#define MIN(a, b) ((a < b) ? (a) : (b))



int partition(vector *v, int p, int r) {

	int x;

	if (p + 3 < r)

		x = MIN(v->elem[p], MAX(v->elem[p+1], v->elem[p+2]));

	else

		x = v->elem[p];

	

	int i = p - 1;

	int j = r + 1;

	while (1) {

		do {

			--j;

		} while (v->elem[j] > x);

		do {

			++i;

		} while (v->elem[i] < x);



		if (i < j) {

			int aux = v->elem[j];

			v->elem[j] = v->elem[i];

			v->elem[i] = aux;

		} else

			return j;			

	}

}



void quicksort_real(vector *v, int p, int r) {

	if (p < r) {

		int q = partition(v, p, r);

		quicksort_real(v, p, q);

		quicksort_real(v, q + 1, r);

	}

}



void quicksort(vector *v) {

	printf("Quicksort...\n");

	quicksort_real(v, 0, v->len - 1);

}

Strange square

scvalex (Alexandru Scvortov) — Mon, 01 Oct 2007 10:02:10 GMT

For n = 8, builds
1 1 1 1 1 1 1 0
1 1 1 1 1 1 0 0
1 1 1 1 1 0 1 0
1 1 1 1 0 0 0 0
1 1 1 0 1 1 1 0
1 1 0 0 1 1 0 0
1 0 1 0 1 0 1 0
0 0 0 0 0 0 0 0

The algorithm, for a n x n matrix is:
1. Split the matrix into 4 matrices of the same size
2. Complete the top-left one with 1
3. Repeat for each of the other 3 matrices.



#include 

#include 



int n;

int **T;



void printM() {

	int i,

		j;

	printf("\n");

	for (i = 0; i < n; ++i) {

		for (j = 0; j < n; ++j)

			printf("%d ", T[i][j]);

		printf("\n");

	}

}



void fill(int x1, int y1, int x2, int y2) {

	printf("%d %d %d %d\n", x1, y1, x2, y2);

	//getchar();

	

	if (x1 == x2) {

		//T[x1][y1] = 1;

		return;

	}

	

	int i,

		j;

	int xm = (x1 + x2) / 2;

	int ym = (y1 + y2) / 2;

	for (i = y1; i <= ym; ++i)

		for (j = x1; j <= xm; ++j)

			T[i][j] = 1;

	

	fill(x1, ym + 1, xm, y2);

	fill(xm + 1, y1, x2, ym);

	fill(xm + 1, ym + 1, x2, y2);

}



int main(int argc, char *argv[]) {

	n = 8;

	T = (int**)malloc(n * sizeof(int*));

	int i;

	for (i = 0; i < n; ++i)

		T[i] = (int*)malloc(n * sizeof(int));

	

	int j;

	for (i = 0; i < n; ++i)

		for (j = 0; j < n; ++j)

			T[i][j] = 0;

	

	fill(0, 0, n - 1, n - 1);

	printM();

	

	return 0;

}

C - Simple Example GTK

whitetiger () — Tue, 05 Dec 2006 16:50:54 GMT

// gcc file.c -o file.o `pkg-config --libs --cflags gtk+-2.0`



#include 

#include 



void displayUI()

{

	GtkWidget* mainWindow = gtk_window_new(GTK_WINDOW_TOPLEVEL);



	gtk_window_set_default_size(GTK_WINDOW(mainWindow), 400, 300);

	gtk_window_set_title(GTK_WINDOW(mainWindow), "GTK Simple Example");

	gtk_window_set_position(GTK_WINDOW(mainWindow), GTK_WIN_POS_CENTER_ALWAYS);



	gtk_signal_connect(GTK_OBJECT(mainWindow), "destroy", G_CALLBACK(gtk_main_quit), NULL);



	gtk_widget_show_all(mainWindow);

}



int main(int argc, char *argv[])

{

	gtk_init(&argc, &argv);



	displayUI();



	gtk_main();



	return EXIT_SUCCESS;

}

Ruby - Sostituire elementi

whitetiger () — Fri, 24 Nov 2006 05:07:55 GMT

// Sostituisce "old" con "new" in tutti i file



ruby .i.bak -pe 'sub "old", "new"' *