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How arrays are passed to functions in C/C++

Posted on Edited on In Disqus:

How arrays are passed to function | Basic and Important

Introduction:

Source code

Idea:

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#include <iostream>
//#include <stdio.h>

using namespace std;
 
// Note that arr[] for fun is just a pointer even if square
// brackets are used
void fun(int arr[])  // SAME AS void fun(int *arr)
{
   unsigned int n = sizeof(arr)/sizeof(arr[0]);
   //printf("\nArray size inside fun() is %d", n);
   //printf("\n - The first value is %d", sizeof(arr));
   
   cout << "nArray size inside fun() is " << sizeof(arr)/sizeof(arr[0]) << endl;
}
 
// Driver program
int main()
{
   int arr[] = {1, 2, 3, 4, 5, 6, 7, 8};
   unsigned int n = sizeof(arr)/sizeof(arr[0]);
   //printf("Array size inside main() is %d", n);
   //printf("\n - The first value is %d", sizeof(arr));
   cout << "nArray size inside main() is " << sizeof(arr)/sizeof(arr[0]) << endl;
   fun(arr);
   return 0;
}