public static int equalStacks(List<Integer> h1, List<Integer> h2, List<Integer> h3) {
    Stack <Integer> stack1 = getStackFromList(h1);
    Stack <Integer> stack2 = getStackFromList(h2);
    Stack <Integer> stack3 = getStackFromList(h3);
    int s1 = getStackSum(stack1);
    int s2 = getStackSum(stack2);
    int s3 = getStackSum(stack3);
    int min = Math.min(s1, Math.min(s2,s3));
    while ((!(s1 == s2 && s1 == s3)) && min>0 ) {
        if (s1 > min) {
            stack1.pop();
            s1 = getStackSum(stack1);
        }
        if (s2 > min) {
            stack2.pop();
            s2 = getStackSum(stack2);
        }
        if (s3 > min) {
            stack3.pop();
            s3 = getStackSum(stack3);
        }
        min = Math.min(s1, Math.min(s2,s3));
        
    }
    return min;

    }
    
    static int getStackSum(Stack<Integer> input) {
       return input.stream()
         .mapToInt(Integer::intValue)
         .sum();
    }
    
    static Stack<Integer> getStackFromList(List<Integer> input) {
        Stack <Integer> stack = new Stack<>();
       for (int i = input.size() - 1; i >=0; i--) {
           stack.push(input.get(i));
       }
       return stack;
    }