二分查找

public class BinarySearch 
{
    
    public static int search(int[] array, int n)
    {
        int low = 0, mid = 0;
        int high = array.length - 1;
    
        while (low <= high) {
            
            mid = (low + high) >> 1;
            
            if (array[mid] == n) 
                return mid;
            
            if (array[mid] > n) 
                high = mid - 1;
            else
                low = mid + 1;
        }
        
        return -1;
    }
    
    
    public static void main(String[] args)
    {
        int[] array = new int[100];
        
        for (int i = 0; i < 100; i++) {
            array[i] = 100 + i;
        }
        
        int result = BinarySearch.search(array, 198);
        
        System.out.println(result);
    }
    
}