public static void plusMinus(List<Integer> arr) {
        // Write your code here
        
        int positiveRatio = 0;
        int negativeRatio = 0;
        int zerosRatio = 0;
        
        int length = arr.size();
        
        for(int num: arr){
            if(num == 0){
                zerosRatio += 1;
            }else if(num > 0){
                positiveRatio += 1;
            }else{
                negativeRatio += 1; 
            }
        }
    
        System.out.printf("%.6f%n", (double) positiveRatio / length);
        System.out.printf("%.6f%n", (double) negativeRatio / length);
        System.out.printf("%.6f%n", (double) zerosRatio / length);
    }