raheelahmad

// partition2.java
// demonstrates partitioning an array
// uses highest-index (right) element as pivot
// to run this program: C>java PartitionApp
////////////////////////////////////////////////////////////////
class ArrayPar
   {
   private long[] theArray;          // ref to array theArray
   private int nElems;               // number of data items
//--------------------------------------------------------------

raheelahmad

<p>There are three threading problems listed <a href="http://www.d.umn.edu/~cprince/courses/cs5631spring10/lectures/ThreadAndSynch.pdf">here</a>. Do all three of them (separately).</p>

<p>This will be due by next Wednesday, Dec. 14th. But, I want you to show me the running code instead of submitting it. Let me know before Monday when you can see me next week.</p>

raheelahmad

- (BOOL) createRelationshipsForDestinationInstance:(NSManagedObject *) destinationAttendance entityMapping:(NSEntityMapping *)mapping manager:(NSMigrationManager *)manager error:(NSError **)error {
	
	NSArray *sourceAttendances = [manager sourceInstancesForEntityMappingNamed:[mapping name] 
														  destinationInstances:[NSArray arrayWithObject:destinationAttendance]];
	NSManagedObject *sourceAttendance = [sourceAttendances objectAtIndex:0];
	
	NSArray *allStudents = [[[sourceAttendance valueForKey:@"theSchedule"] valueForKey:@"theCourse"] valueForKey:@"students"];
	NSArray *presentStudents = [sourceAttendance valueForKey:@"students"];
	NSLog(@"For attendance on %@", [sourceAttendance valueForKey:@"date"]);
	

raheelahmad

totalInversions = 0

countInversions (array, start, end)
	if (start < end)
		int mid = (start + end)/2
		countInversions(array, start, mid)
		countInversion(array, mid+1, end)
		merge(array, start, mid, end)
	// else do nothing	
	

raheelahmad

#import <Foundation/Foundation.h>

@interface MyClass : NSObject

@end

@implementation MyClass

static NSMutableArray *instances;

raheelahmad

import java.util.Random;

public class ThreadingThings implements Runnable{
	
	int myID;
	Random gen;
	
	public ThreadingThings(int anID) {
		myID = anID;
		gen = new Random();

raheelahmad

import java.util.Random;

class Runner implements Runnable {
	public void run() {
		int c = 0;
		while (c++ < 10000)
			if (c % 100 == 0)
				System.out.println("still at " + c);
	}
}

raheelahmad

import java.util.Random;

class Counter {
	private int c=0;
	public synchronized void increment() {
		c++;
	}
	
	public synchronized void decrement() {
		c--;

raheelahmad

One-line Tree in Python

Using Python's built-in defaultdict we can easily define a tree data structure:

def tree(): return defaultdict(tree)

That's it!

raheelahmad

//
//  PersistenceStack.swift

import CoreData

public class PersistenceStack: NSObject {
    let mainContext: NSManagedObjectContext = {
        let context = NSManagedObjectContext(concurrencyType: .MainQueueConcurrencyType)
            context.undoManager = nil
            context.mergePolicy = NSMergeByPropertyObjectTrumpMergePolicy