logo
down
shadow

How to find all ordered pairs of elements in array of integers whose sum lies in a given range of value


How to find all ordered pairs of elements in array of integers whose sum lies in a given range of value

By : user2952927
Date : November 19 2020, 03:59 PM
wish help you to fix your issue Sort the array (say in increasing order). For each element x in the array: Consider the array slice after the element. Do a binary search on this array slice for [a - x], call it y0. If no exact match is found, consider the closest match bigger than [a - x] as y0. Output all elements (x, y) from y0 forwards as long as x + y <= b
The time complexity is of course output-sensitive, but this is still superior to the existing algo:
code :
O(nlogn) + O(k)


Share : facebook icon twitter icon
Find pairs that sum to X in an array of integers of size N having element in the range 0 to N-1

Find pairs that sum to X in an array of integers of size N having element in the range 0 to N-1


By : Billy Bob
Date : March 29 2020, 07:55 AM
I wish this helpful for you No, I don't believe so. You either need extra space to be able to "sort" the data in O(n) by assigning to buckets, or you need to sort in-place which will not be O(n).
code :
  0    1    2    3    4    5    6    7    <- index
(0)7 (0)6 (0)2 (0)5 (0)3 (0)3 (0)7 (0)7
for idx = 0 to N:
    array[array[idx] % 16] += 16 // add 1 to top four bits
  0    1    2    3    4    5    6    7    <- index
(0)7 (0)6 (1)2 (2)5 (0)3 (1)3 (1)7 (3)7
 0   1   2   3   4   5   6   7    <- index
(0) (0) (1) (2) (0) (1) (1) (3)
a b c d e f g h <- identifiers
7 6 2 5 3 3 7 7
(2,6) (3,5) (3,5)
(c,b) (e,d) (f,d) <- identifiers
#include <stdio.h>

int arr[] = {3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5, 8, 9, 4, 4, 4, 4};
#define SZ (sizeof(arr) / sizeof(*arr))

static void dumpArr (char *desc) {
    int i;
    printf ("%s:\n   Indexes:", desc);
    for (i = 0; i < SZ; i++) printf (" %2d", i);

    printf ("\n   Counts :");
    for (i = 0; i < SZ; i++) printf (" %2d", arr[i] / 100);

    printf ("\n   Values :");
    for (i = 0; i < SZ; i++) printf (" %2d", arr[i] % 100);

    puts ("\n=====\n");
}
int main (void) {
    int i, j, find, prod;

    dumpArr ("Initial");

    // Sort array in O(1) - bucket sort.

    for (i = 0; i < SZ; i++) {
        arr[arr[i] % 100] += 100;
    }
    dumpArr ("After bucket sort");

    // Now do pairings.

    find = 8;
    for (i = 0, j = find - i; i <= j; i++, j--) {
        if (i == j) {
            prod = (arr[i]/100) * (arr[i]/100-1) / 2;
            if (prod > 0) {
                printf ("(%d,%d) %d time(s)\n", i, j, prod);
            }
        } else {
            if ((j >= 0) && (j < SZ)) {
                prod = (arr[i]/100) * (arr[j]/100);
                if (prod > 0) {
                    printf ("(%d,%d) %d time(s)\n", i, j, prod);
                }
            }
        }
    }

    return 0;
}
Initial:
   Indexes:  0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16
   Counts :  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0
   Values :  3  1  4  1  5  9  2  6  5  3  5  8  9  4  4  4  4
=====

After bucket sort:
   Indexes:  0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16
   Counts :  0  2  1  2  5  3  1  0  1  2  0  0  0  0  0  0  0
   Values :  3  1  4  1  5  9  2  6  5  3  5  8  9  4  4  4  4
=====

(2,6) 1 time(s)
(3,5) 6 time(s)
(4,4) 10 time(s)
Want to find value which lies within range of array fields

Want to find value which lies within range of array fields


By : Ashveen
Date : March 29 2020, 07:55 AM
like below fixes the issue I think you are misusing the find function. It's far more powerful than you think :p
Actually, find takes only one argument, which is a callback which will be called with three arguments : the element to test, the index of that element, and the array. You will return true if the tested element is valid. documentation here : https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/find
code :
var myElement = User.find(function(element, index, array){
    return element["_id"] == req.params._id && element.reciptBook.startingReciptNumber == {$gte: +req.params.reciptValue};
})
How could I find patterns of repeating pairs of integers in an array or list of integers?

How could I find patterns of repeating pairs of integers in an array or list of integers?


By : Timothy de Vos
Date : March 29 2020, 07:55 AM
hope this fix your issue Assuming you are looking for B to contain a list of all patterns in A that begin on integer x (default at 2), end on integer y (default at -1), and alternate between the values x and y, then here's how you can generate B:
code :
def special_pattern(A, x=2, y=-1):
    B = []
    temp = []
    flag = 0
    for elem in A:
        if elem == x and flag == 0:
            flag = 1
        elif elem == y and flag == 1:
            temp.extend([x, y])
            flag = 0
        else:
            if temp != []:
                B.append(temp)
                temp = []
            if not(elem == x and flag == 1): 
                flag = 0
    if temp != []:
        B.append(temp)
    return B
I am using a numpy array of randomly generated ordered pairs, I need to determin if the ordered pairs are different type

I am using a numpy array of randomly generated ordered pairs, I need to determin if the ordered pairs are different type


By : Tolga Bozkurt
Date : March 29 2020, 07:55 AM
hop of those help? You've described well how you are storing the data, but not what the algorithm is. For example, if we want to answer the question "Is this set of three (x,y) points P1..P3 an equilateral triangle," we can formulate it this way:
code :
dist(P1,P2) == dist(P2,P3) == dist(P3,P1)
sqrt((P1.x - P2.x)**2 + (P1.y - P2.y)**2)
P1.x, P1.y, P2.x, P2.y, P3.x, P3.y
A[0] - A[2] # P1.x - P2.x
A[1] - A[3] # P1.y - P2.y
A[2] - A[4]
A[3] - A[5]
A[4] - A[0]
A[5] - A[1]
R = A - np.roll(A, -2, axis=0) # 1000x6 array of all differences
R[0] + R[1] # (P1.x - P2.x)**2 + (P1.y - P2.y)**2
R[2] + R[3]
R[4] + R[5]
S = R[0::2] + R[1::2] # three column-wise additions at once
np.logical_and(S[0] == S[1], S[1] == S[2])
A = pnts.T
R = np.square(A - np.roll(A, -2, axis=0))
S = R[0::2] + R[1::2] # 1000x3 squares of distances
np.logical_and(S[0] == S[1], S[1] == S[2]) # 1000 True/False results
How to transform in Java an array of ordered pairs in a 2D array of integers

How to transform in Java an array of ordered pairs in a 2D array of integers


By : user3122777
Date : March 29 2020, 07:55 AM
hop of those help? You need to iterate over listOne to retrieve the single D arrays. Then use the values to index into listTwo and set the position.
code :
      int pos = 1;
      int[][] listTwo = new int[10][5];
      for (int r = 0; r < listOne.length; r++) {
         int[] v = listOne[r];
         listTwo[v[0]][v[1]] = pos++;
      }
      for (int[] t : listTwo) {
         System.out.println(Arrays.toString(t));
      }
Related Posts Related Posts :
  • Remove commas in a string, surrounded by a comma and double quotes / Python
  • How to chain Django querysets preserving individual order
  • Comparison with Python
  • How to find backlinks in a website with python
  • Return new instance of subclass when using methods inherited from parent class in Python
  • Which function in django.contrib.auth creates the default model permissions?
  • Formatting text in tabular form with Python
  • How to determine the first day of a month in Python
  • Error while converting date to timestamp in python
  • Python string iterations
  • Is there any file number limitation when you select multiple files with wxFileDialog?
  • Errors with Matplotlib when making an executable with Py2exe (Python)
  • Django Haystack - Indexing single field
  • Go Pro Hero 3 - Streaming video over wifi
  • Appending a column in .csv with Python/Pandas
  • How to change my result directory in Robot framework using RIDE?
  • problem with using pandas to manipulate a big text file in python
  • python-magic module' object has no attribute 'open'
  • Where goes wrong for this High Pass Filter in Python?
  • Why inserting keys in order into a python dict is faster than doint it unordered
  • flann index saving in python
  • Create new instance of list or dictionary without class
  • How can I easily convert FORTRAN code to Python code (real code, not wrappers)
  • Address of lambda function in python
  • Python adding space between characters in string. Most efficient way
  • python http server, multiple simultaneous requests
  • Disguising username & password on distributed python scripts
  • Post GraphQL mutation with Python Requests
  • Why doesnt pandas create an excel file?
  • Rolling comparison between a value and a past window, with percentile/quantile
  • How to avoid repetitive code when defining a new type in python with signature verification
  • How to configure uWSGI in order to debug with pdb (--honour-stdin configuration issue)
  • In Python, how do you execute objects that are functions from a list?
  • Python- Variable Won't Subtract?
  • Processing Power In Python
  • Python 2.7.2 - Cannot import name _random or random from sys
  • Why doesn't the Python sorted function take keyword order instead of reverse?
  • Make a function redirect to other functions depending on a variable
  • get_absolute_url in django-categories
  • Monitoring non-Celery background task with New Relic in Python
  • Feature selection with LinearSVC
  • LSTM - Predicting the same constant values after a while
  • Test the length of elements in a list
  • Django: render radiobutton with 3 columns, cost column must change according to size & quantity selected
  • Python class attributes vs global variable
  • sys.stdout.writelines("hello") and sys.stdout.write("hello")
  • is ndarray faster than recarray access?
  • Python - search through directory trees, rename certain files
  • GAE: How to build a query where a string begins with a value
  • TypeError: __init__() takes at least 2 arguments (1 given)
  • Overriding and customizing "django.contrib.auth.views.login"
  • Django : Redirect to a particular page after login
  • Python search and copy files in directory
  • pretty printing numpy ndarrays using unicode characters
  • Frequent pattern mining in Python
  • How can I make a set of functions that can be used synchronously as well as asynchronously?
  • Convert one dice roll to two dice roll
  • count occourrence in a list
  • Writing an If condition to filter out the first word
  • to read file and compare column in python
  • shadow
    Privacy Policy - Terms - Contact Us © ourworld-yourmove.org