smallest positive integer that does not occur v2.c

/*

    smallest positive integer that does not occur v2.c

    Version without array sort.

    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");
}

// If num exist in arr of n integers, returns 1. Otherwise returns 0.
int ifExist( int num, int arr[], int n){
    int i;

    for(i=0; i<n; i++){
        if( arr[i]==num )
            return 1;
    }
    return 0;
}

int solution( int arr[], int n){
    int num=1;

    while( num <= 1000000 )
        if( ifExist( num, arr, n) == 0 )
            return num;
        else
            num++;

    return num;
}


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

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

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

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

    return 0;
}