So recently I began Data Structures as core subject and the tutorials in this forum are great.
Right now, I seem to have trouble with Big Oh Notation algorithm and what is the mathematical side to it. "f(n) <= c.g(n), for n>=0.
The question I am working on is: Suppose we are maintaining a collection C of elements such that, each time we add a new element to the collection, we copy the contents of C into a new array list of just the right size. What is the running time of adding n elements to an initially empty collection C in this case?
I've been trying to learn more about Big O Notation and I've gotten stuck on a few pieces of code. What is the computational complexity for the following pieces of code?
1:
for(int i = n; i > 0; i /= 2) { for(int j = 1; j < n; j *= 2) { for(int k = 0; k < n; k += 2) { // constant number of operations
[Code] .....
5 : Determine the average processing time of the recursive algorithm. (int n) spends one time unit to return a random integer value uniformly distributed in the range [0,n] whereas all other instructions spend a negligibly small time(e.g., T(0) = 0)
int myTest(int n) { if(n <= 0) return 0; else { int i = random(n - 1); return myTest(i) + myTest(n - 1 - i);
6 : Assume array a contains n values, the method randomValue takes a constant number c of computational steps to produce each output value, and that the method goodSort takes n log n computational steps to sort the array.
with arrays its binary search which finds a value in O(Logn) time but what about linked lists ? the most effiecient algorithm will be O(n) ? and i know that binary search cannot be implement on a linked list , therefore , the only way to search a linked list is a linear search ?
I've to create a program to get user input in scientific notation. Now i'm confused that how can i check that how user have used the scientific notation. For example there are many ways to write a number in scientific notation. Also a user can either write a number as:
6.7E2 OR 6.7*10^2
How to handle this input and further convert it to double?
// the MountainBike subclass has // one field public int seatHeight;
// the MountainBike subclass has // one constructor public MountainBike(int startHeight, int startCadence,
[Code] ....
At first, Java Code: public int seatHeight; mh_sh_highlight_all('java'); tells us that seatHeight is NOT a static field (because of the absence of static keyword).
Whereas in the constructor, the absence of dot notation (like something like this.seatHeight) in Java Code: seatHeight = newValue; mh_sh_highlight_all('java'); shows that it IS a non-member/static variable.
My question is to evaluate a Postfix notation entered from keyboard. I have no errors in my code but it prints only :
Exception in thread "main"
java.util.NoSuchElementException at ArrayStack.pop(PostFixEvaluation.java:72) at PostFixEvaluation.evaluatePostfix(PostFixEvaluatio n.java:107) at PostFixEvaluation.main(PostFixEvaluation.java:140)
I tried many values but it prints the same exception all the time.
So I am supposed to be changing infix notation to postfix notation using stacks. This is simply taking a string "3 + 5 * 6" (infix) and turning it into (3 5 6 * +" (postfix).
To do this, we are to scan the string from left to right and when we encounter a number, we just add it to the final string, but when we encounter an operand, we throw it on the stack. Then if the next operand has a higher input precedence than the stack precedence of the operator on the top of the stack, we add that operator to the stack too, otherwise we pop from the stack THEN add the new operator.
I am supposed to be utilizing a hash map but I don't see how you would go about doing this. We are supposed to store operators on the hash map but operators need their own character, input precedence, stack precedence, and rank. How do you use a hash map when you need to tie a character to 3 values instead of just 1? I just don't get it.
The following is our Operator class that we are to use. Another problem is this isn't really supposed to be modified, yet we were given two important variables (inputPrecedence and outputPrecedence) that we can't have nothing to be initialized to and no way of accessing? So that might be where a hash map comes in but I am not sure. I am not very sure on how they exactly work anyway...
public class Operator implements Comparable<Operator> { public char operator; // operator privateint inputPrecedence; // input precedence of operator in the range [0, 5] privateint stackPrecedence; // stack precedence of operator in the range [-1, 3]
[Code] ....
So my question mostly revolves around how I tie an Operator character to its required values, so I can use it in my code to test two operators precedence values.
My original thought was turn string into character array, but then I would need nested for/while loops to check if it is a number or letter, or if it is an operator and thus result in O(n^2) time
I am working on an assignment that I can't seem to figure out the final part to. The program takes in course data such as the time the class starts and how long it lasts. The time is in military time (0000 - 2400)
I need the output time to be the time the class started, plus the length of the class, and displayed in military time.
I can't for the life of me figure out how to do this. I have gotten a program that works for this time and minutes, and displays the correct 1020. But when I change the information to say
Start time: 0700 Length = 90 minutes
I get:
Endtime = 90
90 is technically correct, the way the formula is setup, but I need it to display 0900 not 90.
Here is the code that I have. Be easy, I'm still learning, and this is just the file I created to get the formula to work. Also, the verbose in here is just for my own debugging to make sure values should be what I'm expecting them to be.
public class calc { public static void main(String[] args) { double hours, minutes, length; double temp; int time = 2400; hours = time / 100; System.out.println("Hours are: " + hours);
I have two classes. time_runner is used for testing my code.
This is what I'm using to test my code:
class time_runner { public static void main(String str[]) throws IOException { Time time1 = new Time(14, 56); System.out.println("time1: " + time1); System.out.println("convert time1 to standard time: " + time1.convert()); System.out.println("time1: " + time1); System.out.print("increment time1 five times: "); time1.increment();
[code]....
The two constructors are "Time()", which is the default constructor that sets the time to 1200, and "Time(int h, int m)" Which says If h is between 1 and 23 inclusive, set the hour to h. Otherwise, set the hour to 0. If m is between 0 and 59 inclusive, set the minutes to m. Otherwise, set the minutes to 0. Those are my two constructors that I pretty much have down. The three methods however I'm having trouble with. The "String toString()" Returns the time as a String of length 4. The "String convert()" Returns the time as a String converted from military time to standard time. The "void increment()" Advances the time by one minute.
public class Time { private int hour; private int minute; public Time(int h, int m) { if(h > 1 && h < 23) hour = h;
Below is the main class of a project ive been working on, the goal is to start a countdown specified by the user. When the countdown reaches zero the base drops in the song that is being played. (Its not done yet) The main problem that arises is the fact that my song plays, and AFTER that, the timer starts.
Output:
Please input countdown in HH:mm:ss format. 00:00:41 Start? Yes
The name of of the song is: Skrillex & Damian "Jr Gong" Marley - "Make It Bun Dem"
The time of base drop is: 00:00:41 //Song starts here
//Song is done //Then timer starts 00:00:41 00:00:40 00:00:39
I would like to set a specific time for a Calendar instance. My below code will set a time one minute ahead of the current time, and format it to ISO8601 standard.
I now want to set another variable(deadlineDate), but to a specific time, say 5 minutes ahead. I would like to hardcode this in so I dont want it to change as a result of getting the instance of the Calendar(which sets it to the current time)
Essentially I am trying to regenerate the above code every minute and increment itself each cycle until it reaches the deadlineDate, which is a fixed datetime.
I am writing a code that tries to figure out the users password by going through every possible key (brute force). Although I think its going to work, it looks EXTREMELY inefficient to me, since its just a huge switch statement for each character -- 94 total, including the shift values. Is there a built in method in the JAVA API that goes through every key or something?
Here is my code for that segment:
public char[] HackingPassword(){ char[] passChars = this.password.toCharArray();//convert the password to char[] char[] hacking = new char[passChars.length];//make the hacking variable same size as users password int nextCharValue = 0;//this is used to cycle through the keyboard //check each letter of hacking to match with password for(int i = 0; i < passChars.length; i++){
Yes my JPanel is not displaying all the time like you would think it would. Before you beat me up yes I am a bit new I am just working on the GUI part of java over my summer break. Obviously it is not suppose to do that. Secondly, As you can see i am using the alphabet to create JButtons. Shouldnt there be an easier way to use a for( loop) . I tried before but I didn't want to get too side tracked.
Java Code:
import javax.swing.*; import java.awt.*; public class hello { private JFrame alphaframe1; private JFrame alphaframe2;
I'm having an issue with this little bit of conversion. I'm converting a string (_dateString) into a Calendar time. I am using DateFormat and SimpleDateFormat to accomplish this task. Everything seems to be working great, except for it figuring out whether it is AM or PM. According to SimpleDateFormat (Java Platform SE 7 ) I am using "aa" to get my AM or PM marker. How come in my output then, it believes it to be 4:45 am instead of 4:45 pm? Hour of Day should return the 24 hour clock, which should show 16 instead of 4. I have posted the output below my code.
Java Code:
import java.text.*; import java.util.*; public class Time{ static String _dateString = "08 Feb 2014, 4:45pm"; public static void main(String args[]){ Calendar cal=Calendar.getInstance();
[Code] ....
Output:
Java Code:
Today is Sat Feb 08 04:45:00 EST 2014 Year: 2014 Month: 1 Day of Month: 8 Day of Week: 7 Week Of Year: 6 Week of Month: 2 Hour: 4 Hour of Day: 4 Minute: 45 Second: 0 Millisecond: 0 mh_sh_highlight_all('java');
I'm working on creating a dice game and getting the users input is giving me a really hard time. I have the main game working but this part I'm stuck on. The problem is that it's not giving me the chance to enter the second input when I ask for the game.
//Create Scanner object Scanner keys = new Scanner(System.in); //Get chips System.out.print("How much money would you like to change? "); int chips = keys.nextInt(); System.out.println("You now have $" + chips + " in chips.");
[code]...
This is what I get when I run it run/How much money would you like to change?
I work as a golf staff I would like to create application which would tell me the playing time and the time when players need to reach certain playing field/hole. my ideas is to make a program which would ask the user to input their starting time and than select the hole number, where the end result would be amount of actuall time.
I have been having hard time to figure out howe to properly structure the input conversion so it is recognized as a time (Exampke: 10:15). Do I need to use the calendar method in Java or ?
I am trying to to insert time onto my jFrame (Netbeans) by using textfields. this is the code i've tried to put into the textfield so whenever i run the program it automatically shows the time.
I Have one query regarding OTP, In my project while registration the otp should be generate and send to the mobile number of user which is registered the form.
