best case complexity of bubble sort code example

Example: interchange sort in system programming

#include<stdio.h>
void BubbleSort(int arr[],int len){
    for(int j = 0 ; j < len-1 ; j ++){
        for(int i = 0; i < len-1 ; i++){
            if(arr[i] > arr[i+1]){
                int temp = arr[i+1];
                arr[i+1] = arr[i];
                arr[i] = temp;
            }
        }
    
    }
    printf("\nBubble Sorted Array : ");
    for(int i = 0; i < len ; i++){
           printf(" %d",arr[i]); 
        }
}
int main(){ 
    printf("Please Enter Size of Array you want to Sort \n > ");
    int len; 
    scanf("%d",&len);
    int arr[len] ;
    for(int i = 0 ; i < len ; i++){
        printf("\n Please Enter %d number of Element of Array \n",i);
        scanf("%d",&arr[i]);
    }
    BubbleSort(arr,len);
    return 0;
}