smallest positive integer that does not occur.c

/*

    smallest positive integer that does not occur.c

    Version with array sort using the qsort() function.

    Task:
    https://www.facebook.com/groups/cprogramming123/permalink/4468570053231257/


    You can find all my C programs at Dragan Milicev's pastebin:

    https://pastebin.com/u/dmilicev

*/

#include <stdio.h>
#include <stdlib.h>

// Function to print array arr of n integers
void PrintArray(char text[],int arr[],int n){
    int i;

    printf("%s",text);
    for(i=0;i<n;i++)
        printf("%5d", arr[i]);

    printf("\n\n");
}

//comparing function for quick sort
int cmpfunc (const void *a, const void *b) {
   return ( *(int*)a - *(int*)b );
}

int solution( int arr[], int n){
    int i, num=0, max=0;

    for(i=0; i<n; i++){
        while(arr[i]<=0 && i<n-1){  // skip no positive values
            printf("\n skipped i=%2d   arr[%d]= %2d   arr[%d]= %2d   max = %d \n", i, i, arr[i], i+1, arr[i+1], max);
            i++;
        }

        if( i<n && max<arr[i] )     // find current max integer
            max=arr[i];

        if ( i<n-1 ){
            printf("\n         i=%2d   arr[%d]= %2d   arr[%d]= %2d   max = %d \n", i, i, arr[i], i+1, arr[i+1], max);

            if( i<n-1 && arr[i+1]-arr[i]>1 ){
                num=max+1;
                break;
            }
        }
    }

    if( num<=0 )
        num=max+1;

    return num;
}


int main(){
    int arr[] = {1,3,6,4,1,2};
//    int arr[] = {1, 2, 3};
//    int arr[] = {-1, -3};
//    int arr[] = {-1, 2, -3};
//    int arr[] = {-1, 4, -3, 2};
//    int arr[] = {-1, 2, -3, 4};
//    int arr[] = {0, 0, 0, 0};
    int n=sizeof(arr)/sizeof(arr[0]);

    printf("\n n = %d \n", n);

    PrintArray("\n        arr = ", arr, n);

    qsort( (void*)arr, n, sizeof(arr[0]), cmpfunc );

    PrintArray("\n sorted arr = ", arr, n);

    printf("\n\n Smallest positive integer that does not occur in arr is %d . \n\n", solution(arr,n) );

    return 0;
}