I want to do an app that, in function of the parameters checked, gives me a random String that I previusly set. The problem isn't the design of the app so the problem is the methods or classes that do what I want.
-I explain my objective with an example:
We have 100 plans to do this weekend. They are in a box and I want to pick randomly one. So great, I suppose that would be more or less easy, but, this weekend is raining so I want to pick a plan that it could be done even if it rains. And it's ending the month and I don't want to spend money so a free plan would be great. Then, I check the boxes "Free plan" and "Raining" and the app gives to me a random plan that meet the conditions.
How would you do that?
I was thinking about a bigs arrays like "Raining plans", "Free plans", with strings inside and when you check the two boxes the arrays were mixed and a string was randomly picked but I don't know how to do that and I think it could be done in another easiest way.
Thanks in advance.
Do with a two dimentional array as follows:
arr[filter][tasks];
let the filter values be binary strings converted to int
say you have two filters as aforementioned "rainy" and "free", the possible vaues are
00 - 0(decimal value 0) - not rainy, not free
01 - 1(decimal value 1) - not rainy, free
10 - 2(decimal value 2) - rainy, not free
11 - 3(decimal value 3) - rainy, free
when user checks both the values, then you have 1 and 1. Now convert binary 11 to integer which would be your first index. Get the random second index for the task.
You can have any number of filters
Hint: Integer.parseInt(binary_str, 2) for binary to int conversion.
Related
sorry for the title but couldn't really express this in another way.
So, let's say I have a variable that represents a prescription's unique code. I already know that there a total of 400 prescriptions. So for every new prescription I would like that code to change by one. The first one I want it to be 001, the second one 002 etc. I know I can just set a static int but how can I make the 0's appear in the front so it prints 001 and not just 1? I am new to java so I might be asking a really stupid question. Thanks for your time!
You can format it with Java format specifiers.
Here would be the code to do that:
int prescriptionCode = 1;
System.out.println(String.format("%03d", prescriptionCode));
The string "%03d" is the format specifier. Going backwards, "d" indicates that the value you want here is a decimal, "3" indicates that you want the value to be 3 characters long regardless of its actual length, "0" means that you want to fill the remaining space the number doesn't take up with 0's.
I'm learning to code by myself (Java and Android) and I'm working on creating an application for Android.
It's a language application (Grammar) to analyze verb.
What I have currently is I have a list of 1000 verb and each one has it's own way of forms and I'm stuck to find way to store them as strings but don't want to use a lot of string or too long array.
I was thinking of array of string but an array to have 1000 string not sure if this is really practical.
I thought of creating what I need in an excel and then to use this excel as the storage where the app can use it to search in it and show the results found there in a TextView but again not quite sure if this will work with Android.
Let's say I have the below 3 verbs in infinitive
Akl
ktv
hlk
Now the first verb can come in another 2 forms (Nakl - Hikel) and the other verbs too have their own forms.
What I want to do is, when a user type the verb whether in past or present for example (Akled "past" or hikeling "present") the system will substring only the verb by removing the ending and then use what is left (for example: akled ---> akl) to show the other forms, in this case if it is "akled" then system will use "akl" and show nakl - hikel.
Example:
User type in text box (akled) and press analyse
System will do the following:
substring the verb only (akl)
then based on this verb will show other forms, which are (nakl - hikel).
Is this doable with huge number of verbs? Let's say each verb has only 2 other forms, so based on this the 1000 verb has 2000 other forms.
Don't bother about loading too many strings in the memory. Strings are internally represented as array of characters and char type in Java takes 2 bytes. So, if you were to keep 100,000 strings (each 20 characters long), then the total memory occupied by the String[] of 100,000 elements will be 100,000 * 20 * 2 = 4,000,000 bytes = 4 MB. And JVM heap size is usually in Gigabytes, so you shouldn't be bothered about whether you should load this much strings in memory or not. Even if you load 10 times the above, i.e. 1,000,000 strings, you'll be occupying only 40 MB of memory.
you can create your own String resource files in android, where you can store there all the strings used on the app: https://developer.android.com/guide/topics/resources/string-resource
above link will show you the format to use, where to put that file of strings in your android project and how to use it.
on this link you have an example of how to get an string array from resources:
https://www.android-examples.com/get-string-array-from-strings-xml-in-android/
I want to take input in the name form like two-third or one-fifth and I want my system to convert it into numerical form and give the answer.
Que: two-third of thirty is?
The system should output 20
How can I program it?
As a general problem natural language processing (NLP) - which is what you're talking about - is a difficult open-ended problem.
There are lots of libraries for this stuff. If you want background look here:
Is there a good natural language processing library
Or look up Natural Language Processing in Wikipedia.
However you said you want to do this and you're new to programming.
The first thing you need to do is break the problem down. That's how we solve programming problems.
So first try writing a program that can read a string containing a single word and map it to a number.
For example "One" outputs 1, "Two" outputs 2, "Thirty" outputs 30.
Next try and write a program that cuts a string into its constituent words.
You probably want to use an array here.
That's a process called tokenizing and Java has a built in StringTokenizer to do that.
You might want to code that yourself, but you're learning and it might be the moment to start learning using library code.
When you've got those try combining them so your program can convert "Thirty Seven" into 37 (i.e. numbers under 100).
That new program should combine the ideas of your program than can convert "Thirty" and "Seven" and the one that can split words up.
This is the other thing we do in programming - combining things.
We break it down to smaller problems solve them and then build them back up to solve the bigger problems.
(I apologize if I'm patronizing you but I have no idea of your experience).
After that you might add logic that handles "Five Hundred And Thirty Seven".
Again, notice how spotting Five followed by Hundred is like converting Five and then finding a token that tells you to multiply what you just saw by 100.
You could go on to handle Thousands, Hundred Thousand etc.
Or you could branch off into the fractions.
That's similar but you just have a different vocabulary.
Seven Forty-Seconds = 7/42.
As a learning challenge I would suggest you'll have come a long way if your program handles things like "forty two ninety-thirds of eight hundred and eighty nine".
The easy solution outputs 0.000508 - the floating point answer to (42/93)*889.
The extra credit solution outputs 2/3937 - (42/93)*889 can be simplified as a rational number to 2/3937.
To be honest, you'll be doing well if you can handle "nine-ninths of ninety nine".
Notice that the first word is the numerator (n). The second is the denominator (d). The third is always 'of'. The forth word is either the tens (t) or the units (u). If the forth was the units you're done otherwise if there is a fifth word it's the units.
The answer in that case is n/d*(t*10+u). If the tens or units are missing they're zero - obviously.
PS: You might need special handling for zero if you object to someone typing in ninety zero. It obviously means ninety but we don't say it in English!
you could try an mapping from
one ->1
two ->2
three ->3
four ->4
and so on
and on the other hand:
half ->2
third ->3
fourth ->4
then create an double to divide first value with 2nd..
at least multiply this value with the third (you can use the first mapping for this value) and you got the result.
At least, it is not easy due to you have to build the mapping between string and int manually.
I want to find a remainder of very long numbers .I am writing a program for this and as I cannot find the remainder directly due to the fact that they are large numbers (in c) .How can I do this?the limit for the number from which I have to divide the bigger number to find remainder is 500.i.e 1 to 500
I thought of dividing the number like this:
1234567=1*10^6+2*10^5+...
1234567%x=1modx*10^6modx+2modx*10^5modx...
I need a better way than this.
Hint:
Use a linked list. Store the number as a group of numbers dynamically.
For eg:
112233445566778899001122 => 11223344 55667788 99001122
Now consider the individual unit and start from left to right. Find the reminder and manipulate it to add to the next group and go on.
Now implementation is very easy :)
Edit:
112233445566778899001122/6 => 11223344 55667788 99001122/6
11223344/6 =>2
2*100000000 + 55667788 = 255667788
255667788/6 => 0
0*100000000 + 99001122 = 99001122
99001122/6=>0
So the reminder is 0.
Remember, the individual unit after manipulation should be under the maximum range int can support.
If your question regards using very long or large numbers try using something a long long. The problem could be that the data type that you are using is too small to hold the values that you require.
You could try using a bignum library like GMP or another kind of ugly way in comparison would be to use arrays or lists, somewhat similar to this.
Other than that, the modulo operation % will calculate the remainder for you.
Sorry if my question sounds dumb. But some time small things create big problem for you and take your whole time to solve it. But thanks to stackoverflow where i can get GURU advices. :)
So here is my problem. i search for a word in a string and put 0 where that word occur.
For example : search word is DOG and i have string "never ever let dog bite you" so the string
would be 000100 . Now when I try to convert this string into INT it produce result 100 :( which is bad. I also can not use int array i can only use string as i am concatinating it, also using somewhere else too in program.
Now i am sure you are wondering why i want to convert it into INT. So here my answer. I am using 3 words from each string to make this kind of binary string. So lets say i used three search queries like ( dog, dog, ever ) so all three strings would be
000100
000100
010000
Then I want to SUM them it should produce result like this "010200" while it produce result "10200" which is wrong. :(
Thanks in advance
Of course the int representation won't retain leading zeros. But you can easily convert back to a String after summing and pad the zeros on the left yourself - just store the maximum length of any string (assuming they can have different lengths). Or if you wanted to get even fancier you could use NumberFormat, but you might find this to be overkill for your needs.
Also, be careful - you will get some unexpected results with this code if any word appears in 10 or more strings.
Looks like you might want to investigate java.util.BitSet.
You could prefix your value with a '1', that would preserve your leading 0's. You can then take that prefix into account you do your sum in the end.
That all is assuming you work through your 10 overflow issue that was mentioned in another comment.
Could you store it as a character array instead? Your using an int, which is fine, but your really not wanting an int - you want each position in the int to represent words in a string, and you turn them on or off (1 or 0). Seems like storing them in a character array would make more sense.