binarySearch

 

Java

while

?

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public class A {     public static int binarySearch(int[] array, int aim) {         int low = 0, high = array.length - 1, mid;         while (low <= high) {             mid = (low + high) / 2;             if (aim < array[mid]) {                 high = mid - 1;             } else if (aim > array[mid]) {                 low = mid + 1;             } else {                 return mid;             }         }         return -(low + 1);     }       public static void main(String[] args) {         int[] array={1,3,5,8};         System.out.println(binarySearch(array,9));     } }

　　

recursion

public class A {
    public static int binarySearch(int[] array, int low, int high, int aim) {
        if (low > high) {
            return -(low + 1);
        }
        int mid = (low + high) / 2;
        if (aim < array[mid]) {
            return binarySearch(array, low, mid - 1, aim);
        } else if (aim > array[mid]) {
            return binarySearch(array, mid + 1, high, aim);
        } else {
            return mid;
        }
    }

    public static void main(String[] args) {
        int[] array = {1, 3, 5, 8};
        System.out.println(binarySearch(array, 0, array.length - 1, 9));
    }
}

 

Go

while

?

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package main   func main() {     var array = []int{1, 3, 5, 8}     println(binarySearch(array, 9)) } func binarySearch(array []int, aim int) int {     var (         low  = 0         high = len(array) - 1         mid  int     )     for low <= high {         mid = (low + high) / 2         if aim < array[mid] {             high = mid - 1         } else if aim > array[mid] {             low = mid + 1         } else {             return mid         }     }     return -(low + 1) }

　　

recursion

?

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package main   func main() {     var array = []int{1, 3, 5, 8}     println(binarySearch(array, 0, len(array)-1, -1)) }   func binarySearch(array []int, low, high, aim int) int {     if low > high {         return -(low + 1)     }     mid := (low + high) / 2     if aim < array[mid] {         return binarySearch(array, low, mid-1, aim)     } else if aim > array[mid] {         return binarySearch(array, mid+1, high, aim)     } else {         return mid     } }