Merging Two Arrays into a Third Using Pointer in C++

[iron galleon]

Hi, I have been struggling to conceptually understand this problem with functions, arrays, and returning a pointer to the dynamically allocated array that contains the merged array.  I would appreciate it if you simplify the core concept in detail. Thank you. Problem: Develop a function that receives two arrays using pass by pointer and their sizes and merges them into a third array. Return the merged array.

[uneven tulip]

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[iron galleon]

hello?

[iron galleon]

please @ me once you have replied

[bold shore]

No one is going to help you unless you show existing code

[bold shore]

[iron galleon]

is it a requirement? i didnt try coding it yet because the logic is confusing

[bold shore]

Yep

[iron galleon]

okay

[iron galleon]

i wasnt sure if i should post a picture instead so i copied pasted it from VS

[copper jungle]

mhmhm since youre talking about merging the arrays I assume you want the output array to also be sorted?
If you just want to combine the arrays you just missed that the secondArray index should also start at 0

[iron galleon]

i dont think the original problem statement provided did not specify that the merged array needs to be sorted. j =0 ? ok i will fix that

i wasnt sure if i understood the concept tho

[bold shore]

!f

[uneven tulip]

#include<iostream>

using namespace std;

int* CombineArrays(int* firstArray, int len1, int* secondArray, int len2) {
  int* CombinedArray = new int[len1 + len2];
  int mergeIndex = 0;

  for (int i = 0; i < len1; i++) {
    CombinedArray[mergeIndex++] = firstArray[i];
  }

  for (int j = 1; j < len2; j++) {
    CombinedArray[mergeIndex++] = secondArray[j];
  }

  return CombinedArray;  // Return combined array
}

int main() {
  int firstArray[] = {1, 3, 5};          // First array
  int secondArray[] = {2, 4, 6, 8, 10};  // Second array

  int* arrayAfterMerge = CombineArrays(firstArray, 3, secondArray, 5);

  for (int i = 0; i < 8; i++) {
    cout << arrayAfterMerge[i] << " ";
  }
  cout << endl;

  delete[] arrayAfterMerge;

  return 0;
}

tun tun

Formatted by Gustavo

[iron galleon]

thanks

[bold shore]

how do you want to implement the merge

[copper jungle]

if we are just talking about combining the arrays
just from looking at the code it looks like you got a pretty good idea of the algorithm

[bold shore]

the first element of secondArray doesn't merge right?

[iron galleon]

combining the elements of the first array with the second array into a new third array. i think

[bold shore]

;compile c++ -includeiostream

[light heath]

Program Output

1 3 5 4 6 8 10 0

gutoguto08 | 33ms | c++ | x86-64 gcc 13.2 | godbolt.org

[iron galleon]

i hope so

[bold shore]

yeah, 2 isn't in here

[copper jungle]

Usually the term merge is used when talking about combining the arrays while preserving the order

[iron galleon]

oh okay i re-write some parts of the code

[bold shore]

your second for loop statement is initialized to 1

[iron galleon]

yea chris told me to change it

i will initialize it to 0

[bold shore]

can you also put that change in the code snipped you sent? #1220122451409895565 message

[iron galleon]

do u want me to send the code again fixed

[bold shore]

edit the previous message

[bold shore]

you can also do that

[iron galleon]

#include<iostream>
using namespace std;

int* CombineArrays(int* firstArray, int len1, int* secondArray, int len2)
{
int* CombinedArray= new int[len1 + len2];
int mergeIndex = 0;

for (int i = 0; i < len1; i++) {
    CombinedArray[mergeIndex++] = firstArray[i];
}

for (int j = 0; j < len2; j++) { 
    CombinedArray[mergeIndex++] = secondArray[j];
}

return CombinedArray; 

}

int main() {

int firstArray[] = { 1, 3, 5 }; 
int secondArray[] = { 2, 4, 6, 8, 10 }; 

int* arrayAfterMerge = CombineArrays(firstArray, 3, secondArray, 5);

for (int i = 0; i < 8; i++) {
    cout << arrayAfterMerge[i] << " ";
}
cout << endl;

delete[] arrayAfterMerge;

return 0;

}

[uneven tulip]

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@iron galleon Has your question been resolved? If so, type !solved :)

[iron galleon]

thanks guys

!solved