Max and min value of array (C pointer)

Question

#include<stdio.h>

void find(int a[], int n, int *min, int *max){
    int tmp, i, j;
    for(i = 0; i < n; i++){
        for(j = i + 1; j < n; j++){
            if(a[i] < a[j]){
                tmp = a[i];
                a[i] = a[j];
                a[j] = tmp;
            }
        }
    }
    *max = *a;
    *min = *(a + n);
    
}

int main(){
    int a[100];
    int n, *min, *max;
    printf("husnegtiinn elementiin toog oruul: ");
    scanf("%d", &n);
    for(int i = 0; i < n; i++){
        scanf("%d", &a[i]);
    }
    find(a, n, min, max);
    printf("ih ni : %d \nbaga ni : %d", *max, *min);
    
}

I am trying to sort the array from user and get the min and max values in those pointers. I am having hard time figuring out how to pass pointers through functions. Am I missing something here?

*(a + n); is outside of the initialized elements in the array. *(a + n - 1) (or simpler a[n-1]) is the last element to which you assigned values. — Ted Lyngmo
– Ted Lyngmo, Commented Dec 18, 2022 at 14:51
The pointers min and max are not initialized, so it's illegal to dereference and assign values like *max = *a. — kotatsuyaki
– kotatsuyaki, Commented Dec 18, 2022 at 14:52

Ted Lyngmo · Accepted Answer · 2022-12-18 14:59:43Z

*(a + n) is outside of the initialized elements in the array. *(a + n - 1) (or simpler a[n-1]) is the last element to which you assigned values.
min and max should not be int*s but ints.

Example:

#include<stdio.h>

void find(int a[], int n, int *min, int *max){
    if(n < 1) return;

    for(int i = 0; i < n; i++){
        for(int j = i + 1; j < n; j++){
            if(a[i] < a[j]){
                int tmp = a[i];
                a[i] = a[j];
                a[j] = tmp;
            }
        }
    }
    *max = a[0];
    *min = a[n - 1]; // the last element
    
}

int main(){
    int a[100];
    int n, min, max; // corrected types
    printf("husnegtiinn elementiin toog oruul: ");

    if(scanf("%d", &n) != 1 || n < 1 || n > 100) return 1;

    for(int i = 0; i < n; i++){
        scanf("%d", &a[i]);
    }
    find(a, n, &min, &max); // take the addresses of `min` and `max`
    printf("ih ni : %d \nbaga ni : %d", max, min);
}

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