Get more info about an IP address or domain name, such as organization, abuse contacts and geolocation.
One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.
Constructing combinations of elements of arrays.
Suppose you have a list of DISTINCT intergers. Store this list of intergers in an array of length LENGTH.
int array[LENGTH] = [0,1,6,34,43,55,...]
const int num;
Suppose num < LENGTH.
int array2[num];
I want to fill array2 with elements of array. That is, I want to pick num DISTINCT elements of array and put them in array2. array2 cannot be filled with the same number.
int array[LENGTH] = [0,1,6,34,43,55,...]
const int num;
Suppose num < LENGTH.
int array2[num];
I want to fill array2 with elements of array. That is, I want to pick num DISTINCT elements of array and put them in array2. array2 cannot be filled with the same number.
Who is Participating?
it is unethical for us to do your schoolwork for you. That is grounds for removal from this site. (for both you and the experts involved.) We can provide only limitied help in accademic assignments. We can answer specific (direct) questions, like you might ask your teacher. We can review your work and post suggestions, again, like your teacher might do.
Do you have specific questions?
Do you have any work on this (incomplete even) that we can review?
Do you have specific questions?
Do you have any work on this (incomplete even) that we can review?
Agreed.
And, erm, is there anything special about how the elements should be picked. Otherwise, just copy them...
And, erm, is there anything special about how the elements should be picked. Otherwise, just copy them...
I am not a computer science student. This is NOT for a course. I am an economics PhD student trying to learn how to use C+ to do evolutionary game theory for a doctoral thesis.
The question above is not trivial to the novice. The statement of the question might not have been clear. I want to RANDOMLY pick num distinct elements from a list of intergers of size length.
As the old proverb goes: if you have nothing useful to say, don't say anything.
The question above is not trivial to the novice. The statement of the question might not have been clear. I want to RANDOMLY pick num distinct elements from a list of intergers of size length.
As the old proverb goes: if you have nothing useful to say, don't say anything.
const int SrcAryLen = 100;
const int DstAryLen = 50;
int SrcAry[SrcAryLen] = {0,1,6,34,....}; // Array to pull from.
int DstAry[DstAryLen]; // Array to fill.
int EffSrcAryLen = SrcAryLen; // length of the source array that can be used.
for (int i = 0; i < DstAryLen; ++i)
{
int SrcPos = rand() % EffSrcAryLen; // Position to pull from.
DstAry[i] = SrcAry[SrcPos]; // Pull a value.
SrcAry[SrcPos] = SrcAry[EffSrcAryLen]; // Put effective last item in position pulled from.
// this step can be skipped if the source array will not
// be reused.
SrcAry[EffSrcAryLen] = DstAry[i]; // Put item pulled from the array
// in the effective last position.
--EffSrcAryLen; // Make the source array effectively smaller.
}
let me know if you have any questions.
const int DstAryLen = 50;
int SrcAry[SrcAryLen] = {0,1,6,34,....}; // Array to pull from.
int DstAry[DstAryLen]; // Array to fill.
int EffSrcAryLen = SrcAryLen; // length of the source array that can be used.
for (int i = 0; i < DstAryLen; ++i)
{
int SrcPos = rand() % EffSrcAryLen; // Position to pull from.
DstAry[i] = SrcAry[SrcPos]; // Pull a value.
SrcAry[SrcPos] = SrcAry[EffSrcAryLen]; // Put effective last item in position pulled from.
// this step can be skipped if the source array will not
// be reused.
SrcAry[EffSrcAryLen] = DstAry[i]; // Put item pulled from the array
// in the effective last position.
--EffSrcAryLen; // Make the source array effectively smaller.
}
let me know if you have any questions.
Question has a verified solution.
Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.
Have a better answer? Share it in a comment.
All Courses
From novice to tech pro — start learning today.
-
Course of the Month11 days, 1 hour left to enrollMonitoring and Operating a Private Cloud with System Center 2012 R2 273 lessons
Its relatively easy to randomly pull items from one array and place them in another. The hard part is making sure that you don't pull the same item twice. To accomplish this, you will effectively shrink the array each time an item is pulled from it. To do this when you pull an item from the array you will sawp the item witht eh item at the "effective" end of the array and then shrink the "effective" size of the array by 1 so the item is no longer in the effective array.
code sample follows.