How to pass a full array in an array of pointers - c

Question

I wrote a program that sorts the values of an array. It has 5 arrays,
int arr1[] = { 3, 9, 6, 7 };
int arr2[] = { 2, 5, 5 };
int arr3[] = { 0 };
int arr4[] = { 1, 6 };
int arr5[] = { 4, 5, 6, 2, 1 };
and an array of pointers that holds those 5 arrays,
int* pArr[LEN] = { arr1, arr2, arr3, arr4, arr5 };
I want to sort the values of each array, but when I pass the arrays to the sorting function
sortArrValues(&pArr[i]);
it sees the first index of each array (arr1,arr2...) as the element of that array (pArr[i]), so pArr[i] is (3,2,0,1,4).
But I want pArr[i] to be the full array it meant to be, so in the first iteration pArr[i] will be (3,9,6,7).
Notes: the first index of each array indicates the length of that array (not including that index).
The sorting will skip the first index.
There are two additional functions,they're not used (you can skip them).
Here's the full code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define LEN 5
void sortArrValues(int** arr);
void sortArrAdress(int* pArr);
void printArr(int * pArr);
int main()
{
int arr1[] = { 3, 9, 6, 7 };
int arr2[] = { 2, 5, 5 };
int arr3[] = { 0 };
int arr4[] = { 1, 6 };
int arr5[] = { 4, 5, 6, 2, 1 };
int* pArr[LEN] = { arr1, arr2, arr3, arr4, arr5 };
int i = 0;
for (i = 0; i < LEN; i++)
{
sortArrValues(&pArr[i]);
}
//sortArrAdress(pArr);
//printArr(pArr);
return 0;
}
/*
this function will sort the given arrays' values.
in: array
out: none
*/
void sortArrValues(int** arr)
{
int tmp = 0;
int i = 0;
for (i = 1; i < *arr; i++)
{
if (*arr[i] > *arr[i+1])
{
tmp = *arr[i];
*arr[i] = *arr[i + 1];
*arr[i + 1] = tmp;
}
}
}

Answer 1

There is some errors in your code.
First, you don't need to send &pArr[i], pArr[i] is enough to order your arrays. then your void sortArrValues(int** arr) become void sortArrValues(int* arr) which is clearer to read.
Second, in your sortValues, you when you change a value, you should restart (I know that's not very optimized but if you would want to make something really faster, you should use a quick sort. with your code, { 4, 5, 6, 2, 1 } will become { 4 5 2 1 6 }.
So that's your code with the fixes:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define LEN 5
void sortArrValues(int* arr);
void sortArrAdress(int* pArr);
void printArr(int * pArr);
int main()
{
int arr1[] = { 3, 9, 6, 7 };
int arr2[] = { 2, 5, 5 };
int arr3[] = { 0 };
int arr4[] = { 1, 6 };
int arr5[] = { 4, 5, 6, 2, 1 };
int* pArr[LEN] = { arr1, arr2, arr3, arr4, arr5 };
int i = 0;
for (i = 0; i < LEN; i++)
{
sortArrValues(pArr[i]);
}
//sortArrAdress(pArr);
//printArr(pArr);
for (int i = 0 ; i < LEN ; i++) {
for (int j = 0 ; j < pArr[i][0] + 1 ; j++)
printf("%d ", pArr[i][j]);
printf("\n");
}
return 0;
}
/*
this function will sort the given arrays' values.
in: array
out: none
*/
void sortArrValues(int* arr)
{
int tmp = 0;
int i = 0;
for (i = 1; i < *arr; i++)
{
if (arr[i] > arr[i+1])
{
tmp = arr[i];
arr[i] = arr[i + 1];
arr[i + 1] = tmp;
i = 0;
}
}
}

Answer 2

I tried to modify your program to fix issues. Some of these issues are already highlighted by others. There were some there were not. Here is the working snippet. Let me know if you need more explanation on any modification. Note that I have only modified your sort function. The idea is not to give you the fastest sorting algorithm, but a working one.
int main()
{
int arr1[] = { 3, 9, 6, 7 };
int arr2[] = { 2, 5, 5 };
int arr3[] = { 0 };
int arr4[] = { 1, 6 };
int arr5[] = { 4, 5, 6, 2, 1 };
int* pArr[] = { arr1, arr2, arr3, arr4, arr5 };
int i = 0;
for (i = 0; i < LEN; i++)
{
sortArrValues(&pArr[i]);
}
}
void sortArrValues(int** arr)
{
int tmp = 0;
int i = 0, j = 0;
for (i = 0; i < (**arr) - 1; i++)
{
for(j=i+1; j < (**arr) - 1; j++) {
if ((*arr)[i+1] > (*arr)[j+1])
{
tmp = (*arr)[i+1];
(*arr)[i+1] = (*arr)[j + 1];
(*arr)[j+1] = tmp;
}
}
printf("%d ", (*arr)[i+1]);
}
printf("%d\n", (*arr)[i+1]);
}