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Best way to merge two maps and sum the values of same key?
...tor over any duplicate values. The standard semigroup for Int uses the addition operator, so you get the sum of values for each duplicate key.
Edit: A little more detail, as per user482745's request.
Mathematically a semigroup is just a set of values, together with an operator that takes two valu...
How to resolve “Error: bad index – Fatal: index file corrupt” when using Git
After git init , I added and committed a few files, made some changes, added and committed. Set up the git daemon (running under Cygwin on WinXP) and cloned the repository once.
Now, I get this error with the cloned repository:
...
Do git tags get pushed as well?
Since I created my repository it appears that the tags I have been
creating are not pushed to the repository. When I do git tag on the
local directory all the tags are present, but when I logon to the
remote repository and do a git tag , only the first few show up.
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Should Github be used as a CDN for javascript libraries? [closed]
Serving javascript libraries from a CDN instead of your own server comes with tremendous advantages. Less work for your server, possibility for the CDN to have a copy closer to the user than your server, but most importantly a good chance that your user's browser already has it cached from that URL...
How to export DataTable to Excel
... to Excel in C#? I am using Windows Forms. The DataTable is associated with a DataGridView control. I have to export records of DataTable to Excel.
...
What is your favorite C programming trick? [closed]
...ues) {
while(*values) {
x = *values++;
/* do whatever with x */
}
}
func((type[]){val1,val2,val3,val4,0});
Static linked lists
int main() {
struct llist { int a; struct llist* next;};
#define cons(x,y) (struct llist[]){{x,y}}
struct llist *list=cons(1, cons(2,...
Why does “return list.sort()” return None, not the list?
...verify that the findUniqueWords does result in a sorted list . However, it does not return the list. Why?
7 Answers
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Difference between static memory allocation and dynamic memory allocation
... when the program starts. The size is fixed when the program is created. It applies to global variables, file scope variables, and variables qualified with static defined inside functions.
Automatic memory allocation occurs for (non-static) variables defined inside functions, and is usually store...
Why can I access private variables in the copy constructor?
I have learned that I can never access a private variable, only with a get-function in the class. But then why can I access it in the copy constructor?
...
Data structure: insert, remove, contains, get random element, all at O(1)
...e keys are the elements in the data structure, and the values are their positions in the array.
insert(value): append the value to array and let i be its index in A. Set H[value]=i.
remove(value): We are going to replace the cell that contains value in A with the last element in A. let d be the la...