Reputation: 303
Hey i am trying to print largest element in an array using function and pointers. Below is my code but its printing garbage value. Please help.
void findmax(int arr[],int,int*);
void findMax(int arr[], int n, int* pToMax)
{
if (n <= 0)
return; // no items, no maximum!
int max = arr[0];
pToMax = &arr[0];
for (int i = 1; i < n; i++)
{
if (arr[i] > max)
{
max = arr[i];
pToMax = (arr+i);
}
}
}
int main()
{
int nums[4] = { 5, 3, 15, 6 };
int *ptr;
findMax(nums, 4, ptr);
printf("The maximum is at address %u\n", ptr);
printf("It's at index %d\n",ptr - nums);
printf("Its value is %d\n", *ptr);
}
Upvotes: 1
Views: 177
Reputation: 47784
With int *pToMax
in findMax(int arr[], int n, int* pToMax)
and
calling as findMax(nums, 4, ptr);
you just pass ptr
as a value.
The updated value won't be reflected after function exits.
You need to use **pToMax
to save address.
void findMax(int arr[], int n, int** pToMax)
{
if (n <= 0)
return; // no items, no maximum!
int max = arr[0];
*pToMax = &arr[0]; //Store base address
for (int i = 1; i < n; i++)
{
if (arr[i] > max)
{
max = arr[i];
*pToMax = (arr+i); //Store max address
}
}
}
call using
findMax(nums, 4, &ptr);
Upvotes: 4