public int freeParks(String street) {
		int answer = 0;
	    char[] st = street.toCharArray();
	    int n = st.length;
	    System.out.println(n);
	    for(int i = 0;i < n;i++){
	    	if(st[i] == '-'){
	    		if(i+1 < n)
	    		{
	    			if(st[i+1] == 'B'){
	    				continue;
	    			}
	    		}
	    		if(i+2 < n){
	    			if(st[i+2] == 'B'){
	    				continue;
	    			}
	    		}
	    		if(i+1 < n){
	    			if(st[i+1] == 'S'){
	    				continue;
	    			}
	    		}
	    		if(i-1 >=0 ){
	    			if(st[i-1] == 'S'){
	    				continue;
	    			}
	    		}
	    		answer++;
	    		}
	    	}
		return answer;
	}