Generating Unique Random Numbers Using Java

When you generate random numbers its often the case that each generated number number must be unique. A good example is picking lottery numbers. Each number picked randomly from a range (e.g., 1 to 40) must be unique, otherwise, the lottery draw would be invalid. Using a Collection The easiest way to pick unique random numbers is to put the range of numbers into a collection called an ArrayList. If youve not come across an ArrayList before, its a way of storing a set of elements that dont have a fixed number. The elements are objects that can be added to or removed from the list. For example, lets make the lottery number picker. It needs to pick unique numbers from a range of 1 to 40. First, put the numbers into an ArrayList using the add() method. It takes the object to be added as a parameter: import java.util.ArrayList;public class Lottery { public static void main(String[] args) { //define ArrayList to hold Integer objects ArrayList numbers new ArrayList(); for(int i 0; i 40; i) { numbers.add(i1); } System.out.println(numbers); }} Note that we are using the Integer wrapper class for the element type so that the ArrayList contains objects and not primitive data types. The output shows the range of numbers from 1 to 40 in order: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40] Using the Collections Class A utility class called Collections offers different actions that can be performed on a collection like an ArrayList (e.g., search the elements, find the maximum or minimum element, reverse the order of elements, and so on). One of the actions it can perform is to shuffle the elements. The shuffle will randomly move each element to a different position in the list. It does this by using a Random object. This means its a deterministic randomness, but it will do in most situations. To shuffle the ArrayList, add the Collections import to the top of the program and then use the Shuffle static method. It takes the ArrayList to be shuffled as a parameter: import java.util.Collections;import java.util.ArrayList;public class Lottery {public static void main(String[] args) {//define ArrayList to hold Integer objectsArrayList numbers new ArrayList();for(int i 0; i 40; i){numbers.add(i1);}Collections.shuffle(numbers);System.out.println(numbers);}} Now the output will show the elements in the ArrayList in a random order: [24, 30, 20, 15, 25, 1, 8, 7, 37, 16, 21, 2, 12, 22, 34, 33, 14, 38, 39, 18, 36, 28, 17, 4, 32, 13, 40, 35, 6, 5, 11, 31, 26, 27, 23, 29, 19, 10, 3, 9] Picking the Unique Numbers To pick the unique random numbers simply read the ArrayList elements one by one by using the get() method. It takes the position of the element in the ArrayList as a parameter. For example, if the lottery program needs to pick six numbers from the range of 1 to 40: import java.util.Collections;import java.util.ArrayList;public class Lottery {public static void main(String[] args) {//define ArrayList to hold Integer objectsArrayList numbers new ArrayList();for(int i 0; i 40; i){numbers.add(i1);}Collections.shuffle(numbers);System.out.print(This weeks lottery numbers are: );for(int j 0; j 6; j){System.out.print(numbers.get(j) );}}} The output being: This weeks lottery numbers are: 6 38 7 36 1 18

Baseball Is One Of America s Greatest Pastimes And The...

Baseball is one of America’s greatest pastimes and an iconic game that captures the imaginations of all age groups. Today, baseball is one of the most popular sports in the world and the aura of the game brings people together from many diverse backgrounds across the globe. There are many different elements that bring fans to the ballpark to watch their favorite teams and many of these elements are not directly correlated with the on-field action of the game. The atmosphere at a baseball game is fun, relaxing, and enjoyable because of the numerous attractions especially in the new modern ballparks across America. There is the food attraction which has become a staple across American dining cuisine simply know as ballpark food.†¦show more content†¦Major League Baseball continues to adapt to the ever changing technological landscape as the fan’s attention span gets shorter the more and more options teams have to present in terms of connect ability and entert ainment. â€Å"One common explanation is that in an age of ever increasing speed and shrinking attention spans, the pace of baseball games is just too slow† (Taylor). The attempt to link technology to a Major League fan to the live action is what top baseball executives are determined to achieve while gaining critical customer relationship management data. CRM generates an organization’s sales leads, marketing targets, and many other important tools utilized throughout the business processes. â€Å"Nowadays, fans can buy their tickets on an MLB team’s website, follow the tweets of players, â€Å"like† behind-the-scenes photos a team posts on Facebook, comment on a manager’s moves on team-supervised blogs and get updates on open seats, new merchandise and weather for the first pitch. In turn, teams hope that by communicating through social media outlets, they can better know their fans and build a loyal customer base, win or lose† (McKeon).

Revenge of the Spaniards free essay sample

Analysis of Bernal Diazs The Conquest of New Spain. This paper presents an in-depth analysis of Bernal Diazs The Conquest of New Spain. The paper examines the shroud of mystery surrounding the details of Montezumas death and, by utilizing the opinions of David Boruchoff and the actual text of Diazs book, this paper briefly highlighting the key points that Diaz makes in his retelling of Montezumas unfortunate murder. The paper then brings to light the rational faults and discrepancies within the original text and counters these apparent errors, by applying common sense and general knowledge of the era. The readable report, a concept from Joseph Conrads Heart of Darkness, is easily applicable to Bernal Diazs The Conquest of New Spain. The aforementioned readable report, in a general sense, indicates that the retelling of a situation or event is portrayed in a manner that benefits the teller even if distortion of the truth is required. We will write a custom essay sample on Revenge of the Spaniards or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page Diaz, in his account of Montezumas death, makes the Spanish appear blameless and seemingly innocent of Montezumas blood. Throughout the sequence of events leading up to Montezumas death, there are constant indictments of the Mexicans causing the death of their own leader.

My Love, My Log free essay sample

Im that person who writes a 248 word essay when the prompt allows me to write up to 250 words, sorry admissions officers. I have this strange need to write, its like a drug, I have withdrawals. A piece of paper almost seduces me, sitting there tempting me with its horrendously magnificent blank stare. A lot of people ask me what I write. I write everything. Anything you could conjure up in your mind, I have written about it. I can be serious and write a direct stream of consciousness. It usually ends up reading like a typical teenage brain: rebelling, provoking, questioning. Although writers are stereotypically very serious about their work, I can be the outlier at times. For example, I have a poop log that I write in. Which basically means that, yes, I can be immature at times and, yes, poop logs do exist. I can go from writing responses to Nietzsches philosophies to rating a bathroom session on a 1-10 scale. We will write a custom essay sample on My Love, My Log or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page Basically, my writing represents me entirely, humorous and thoughtful. Please dont misunderstand, I take myself very seriously, and I would be lost if my thoughts decided to stop plaguing my mind. But, at the same time laughing is the foot that kicks me out of bed every morning. If you can make me laugh until I cant breathe, then youre my friend. Writing is my niche, my love, and my passion. Let me be Jean Paul Sartre and let me be Spongebob Squarepants!