unique

问题 How can i find only the elements that appears once in the list and return the cardinal number?For example if my list consist of {3,2,1,1,2,4} i expect for return the counter to be 4 and not 6 cause we do not count the duplicate numbers. Here is the code that i have written so far. struct Node { int data; struct Node *next; }; int Find_cardinal(struct Node *start) { struct Node *ptr1, *ptr2 ptr1 = start; int counter=0; /* Pick elements one by one */ while (ptr1 != NULL && ptr1->next != NULL) {

问题 I try to remove the Integer duplicates of a List of (String, Int) , where I am guaranteed that there is no String duplicate. Is it possible to evaluate something like this in Haskell: I tried: [(a,b) | (a,b) <- bs, (c,k) <- bs, ((k == b) <= (a == c))] but this does not yet work. Edit: I am well aware, that you can achieve that using more complex syntax. For example by recursively searching the List for each elements duplicates... 回答1: (NB: this is a completely new version of this answer.

问题 I try to remove the Integer duplicates of a List of (String, Int) , where I am guaranteed that there is no String duplicate. Is it possible to evaluate something like this in Haskell: I tried: [(a,b) | (a,b) <- bs, (c,k) <- bs, ((k == b) <= (a == c))] but this does not yet work. Edit: I am well aware, that you can achieve that using more complex syntax. For example by recursively searching the List for each elements duplicates... 回答1: (NB: this is a completely new version of this answer.

问题 Closed . This question needs details or clarity. It is not currently accepting answers. Want to improve this question? Add details and clarify the problem by editing this post. Closed 19 days ago . Improve this question I need a function that could be called uniqueBy that would remove all elements in a list of tuples that have the same snd value, without keeping even one of them as nubBy would. For example, uniqueBy [(1,1),(2,1)] should return [] , whereas uniqueBy [(1,1),(1,1),(1,2)] would

问题 I am looking for something similar to the bash command comm, that I can use to select entries both unique to my 2 files and common to them. Comm worked great when I had just one column per file, eg. comm -13 FILE1.txt FILE2.txt > Entries_only_in_file1.txt But now I have multiple columns of info I wish to keep. I want to select column 2 as the one to filter rows for unique and common entries between my two files. If the entry in column two appears in both files I also want to record the info

问题 I am looking for something similar to the bash command comm, that I can use to select entries both unique to my 2 files and common to them. Comm worked great when I had just one column per file, eg. comm -13 FILE1.txt FILE2.txt > Entries_only_in_file1.txt But now I have multiple columns of info I wish to keep. I want to select column 2 as the one to filter rows for unique and common entries between my two files. If the entry in column two appears in both files I also want to record the info

问题 I have an array of Objects that have 6 properties. That look like this: $csvData CURRENT DATE AND TIME : 07/10/2015 08:17:17 CST USER NAME : userName COMPUTER NAME : computerName IP ADDRESS : 192.168.1.1 LOGON SERVER : logonServer LOGON/OFF : logon I want to create an array of objects where username and computer name are not duplicated. How can I get only the unique username/computername combo in powershell? Ultimately I would like to remove all duplicates and add a property 'Count' that

问题 I have an array of Objects that have 6 properties. That look like this: $csvData CURRENT DATE AND TIME : 07/10/2015 08:17:17 CST USER NAME : userName COMPUTER NAME : computerName IP ADDRESS : 192.168.1.1 LOGON SERVER : logonServer LOGON/OFF : logon I want to create an array of objects where username and computer name are not duplicated. How can I get only the unique username/computername combo in powershell? Ultimately I would like to remove all duplicates and add a property 'Count' that

来源： https://stackoverflow.com/questions/49796271/find-intersection-of-two-columns-in-python-pandas-list-of-strings

来源： https://stackoverflow.com/questions/49796271/find-intersection-of-two-columns-in-python-pandas-list-of-strings