1、二分查找
时间复杂度 O(logn)
public static int erFenSearch(int key,int[] array,int low,int high) {
int middle = (low + high) / 2;
if(key < array[low] || key > array[high] || low>high) {
return -1;
}
if(array[middle] > key) {
high = middle-1;
return erFenSearch(key,array,low,high);
}else if(array[middle] < key){
low = middle+1;
return erFenSearch(key,array,low,high);
}else {
return middle;
}
}