remove duplicate words

Today there is a new requirement, and one department needs to get data from MongoDB, requiring that one of the fields be stripped of the same content.Although MongoDB distinct come and go, but unlike MySQL's distinct, MySQL can use distinct * to return the entire record of information, And MongoDB's distinct I just return to the data of the field of the heavy (perhaps MongoDB can also return the whole article, but I do not know).Distinct in MySQL returns the full record:Distinct in MongoDB to re

Tags: sql StackOverflow de-weightproblemSuppose you have a table with a larger amount of data (for example, 300,000+ rows), where there are duplicate rows (other than the primary key, the other column data is the same), how do you quickly go heavy? My watch looks like this.MyTable-----------RowID int not null identity(1,1) primary key,Col1 varchar(20) not null,Col2 varchar(2048) not null,Col3 tinyint not nullEssence AnswerAssuming there are no null va

), Cyclic value assignment $ output [$ k] [$ keyname_Arr [$ tempk] = tempv; 6. finally, $ output is the two-dimensional array after deduplication. Let's take a look at the actual code: $ Keyname_Arr = array_keys (end ($ resource_arr )); // key name for storing the inner array // use '-' as the separator to concatenate the array into a string foreach ($ resource_arr as $ v) {$ v = join ("-", $ v); $ temp [] = $ v;} // remove the

Php two-dimensional array remove repeated items of a specific key no two-dimensional array remove repeated items of a specific key publicfunctionarray_unset ($ arr, $ key) {$ arr-input array $ key-the key value to be judged to create a target array $ resarray (); foreach ($ arras $ value) {check whether there are repeated items if (isset ($ res [$ value [$ ke Php two-dimensional array removes repeated items

The original title link is here: https://leetcode.com/problems/remove-duplicate-letters/Topic:Given a string which contains only lowercase letters, remove duplicate letters so this every letter appear once and only O nCE. You must make sure your result are the smallest in lexicographical order among all possible result

Here's a summary of two ways to remove duplicate data from an array in PHP 1. Direct use of the Array_unique function The Array_unique function allows you to remove duplicate values directly from an array, preserving only the first occurrence of values and their corresponding key values in a repeating value.

Three kinds of Java remove duplicate character functions from strings*/ public static void Main (string[] args) {System.out.println (Removerepeatedchar ("DDDDCCFFGD"));} public static string Removerepeatedchar (string s) {if (s = = null)return s; StringBuilder sb = new StringBuilder (); int i = 0, Len = s.length (); while (i char c = s.charat (i); Sb.append (c); i++; while (i i++;

The syntax of regular expressions is known for its simplicity and efficiency, but one point I is more complex. There is a recent feature that needs to be removed from the repeated parts of the string, because using the normal traditional kind of comfortable split into an array in one matching way feels a bit inefficient and wasteful, and then thinks of a regular expression to match a duplicate string, The string is replaceall by using string-guided me

Given a string which contains only lowercase letters, remove duplicate letters so this every letter appear once and only O nCE. You must make sure your result are the smallest in lexicographical order among all possible results.Example:Given"bcabc"Return"abc"Given"cbacdcbc"Return"acdb"The runtime is O (-* N) = O (n). Public classSolution {//form a dictionary int[26]//find the smallest value in the current S

-- Function: Provides replacement Aggregate functions for strings. -- Note: for example, convert the following data -- Test_id test_value -------------------- 'A' 01, 03,04' 'A' 02, 04' 'B' 03, 04, 08' 'B' 06, 08,09' 'C' '09' 'C' '10' -- Convert to the aggregate function of the test_vlaue column, and the values in the aggregated string are not repeated. -- Test_id test_value--------------------'A' 01, 03,04, 02''B' 03, 04, 08, 06, 09''C' 09, 10' --Code---------------------------------------

Provide string replacement Aggregate functions Provide string replacement Aggregate functions -- Function: Provides replacement Aggregate functions for strings. -- Note: for example, convert the following data -- Test_id test_value -------------------- 'A' 01, 03,04' 'A' 02, 04' 'B' 03, 04, 08' 'B' 06, 08,09' 'C' '09' 'C' '10' -- Convert to the aggregate function of the test_vlaue column, and the values in the aggregated string are not repeated. -- Test_id test_value -------------------- 'A' 0

-- Function: Provides replacement Aggregate functions for strings.-- Note: for example, convert the following data-- Test_id test_value--------------------'A' 01, 03,04''A' 02, 04''B' 03, 04, 08''B' 06, 08,09''C' '09''C' '10'-- Convert to the aggregate function of the test_vlaue column, and the values in the aggregated string are not repeated.-- Test_id test_value--------------------'A' 01, 03,04, 02''B' 03, 04, 08, 06, 09''C' 09, 10'-- Code ------------------------------------------- GOGOIf obj

First, we use the merge sort algorithm to sort the array, the time complexity is O (Nlogn), and then use the time complexity O (n) de-duplication algorithm to remove the repeating elements in the arrays. The total time complexity is O (NLOGN).(This problem should be solved by branching algorithm) The following is the branching algorithmCode is not a branching algorithm1 PackageOrg.xiu68.ch02.ex2;2 3 Public classex2_14 {4 //merging sorting algori

Very little said, JS array to remove duplicate data from the code below: var arr = [1,2,3,4,5,6,1,6,7,2]; var newArr = []; for (var i =0;i Here to share the high efficiency remove the JS array duplicates The array type does not provide a way to repeat, if you want to kill the repeating elements of the array, you have to do it yourself: fun

Remove duplicate records from mongodb group query statistics The mongodb version is, MongoDB shell version: 2.4.4The operating environment and shell window are as follows: [mongo_user@mongodb_dbs ~]# mongo --port 30100MongoDB shell version: 2.4.4connecting to: 127.0.0.1:30000/testmongos> mongos> use posswitched to db posmongos> 1. count the number of group records first, and use the paymentOrder field to g

For a fixed known array such as:var arr = [' name ', ' OK ', ' 123 ', ' n ', ' look ', ' 777 ', ' n ', ' 123 ', ' name ', 1,3,5,1, ' OK '];So the question is, how can we get rid of the duplicate strings or numbers, getting a new array?Method ①:function takerepetition_1 (arr) {var data= {}; //This will traverse the data's arr[i] property because the data is empty for the return undefined var result = [];For (Var i=0;iif (!json[arr[i]]) {Json[arr[i]] =

The following small series will provide you with a JavaScript array to remove duplicate values. I think it is quite good. Now I will share it with you and give you a reference. It is a common requirement to repeat arrays together with a small Editor. We will temporarily consider repeat arrays of the same type. It mainly aims to clarify the ideas and consider the performance. The following methods are availa

(array) {var n = {},r = [],val,type;for (var i = 0;i val = array[i];Type = typeof Val;if (!n[val]) {N[val]=[type]R.push (Val)}else if (N[val].indexof (type) N[val].push (Type)R.push (Val)}}return R;}3. Array subscript Judgment methodIdea: If the current array of item I is in the current array the first occurrence of the position is not I, then the term I is repeated, ignored, otherwise deposited in the result arrayfunction Unique3 (array) {var n = [Array[0]]for (var i = 1;i if (Array.indexof (a

original elements of the array while deleting the duplicate elements, Del. Idea two: Create an array b, push the elements in a to B, but check that the element exists before the push. This time complexity is n*n, the simplest is the most stupid way. Train of thought three: similar to train of thought, but make full use of the properties of the JS object, create a new empty object, add the element in a as a property to the object, and detect whether t

1. Remove duplicate string elements from the ArrayList collection (same string content)Analysis:(1) Creating a Collection Object(2) Adding multiple string elements (containing duplicates)(3) Create a new collection(4) Iterate through the old collection to get each element(5) Take an element to the new set and look for it.Have: ignore itNo: Add to new collection(6) Traversing a new collection2. Case code:1