Javacollections已经内置了一些常用算法，此处作为标记，方便温故而知新

1、二分查找

public class BinarySearch {
    public static <T> int binarySearch(List<? extends Comparable<? super T>> list, T data) {
        int start = 0;
        int end = list.size() - 1;
        while (start <= end) {
            int mid = (end + start) >>> 1;
            Comparable<? super T> midVal = list.get(mid);
            if (midVal.compareTo(data) == 0) {
                return mid;
            } else if (midVal.compareTo(data) > 0) {
                end = mid - 1;
            } else {
                start = mid + 1;
            }
        }
        return -1;
    }

    public static void main(String[] args) {
        int i = binarySearch(Arrays.asList(1, 2, 3, 6, 8, 44, 99, 145), 18);
        System.out.println(i);
    }
}

2、斐波拉契数列（Fibonacci），除第一个和第二个数外，任意一个数都可由前两个数相加得到

public class FibonacciDemo {
    public static ArrayList<Integer> fib(int size) {
        int a = 0;
        int b = 1;
        //中间结果标记
        int n = 0;
        //数组长度计数器
        int len = 0;
        ArrayList<Integer> nums = new ArrayList<>();
        while (len <= size) {
            len++;
            n = a + b;
            nums.add(n);
            a = b;
            b = n;
        }
        return nums;
    }

    public static void main(String[] args) {
        ArrayList<Integer> fibList = fib(10);
        System.out.println(fibList);
    }
}