int binarySearch(int[] A, int low, int high, int x)
{
if (low > high) {
return -1;
}
int mid = (low + high) / 2;
if (x == A[mid]) {
return mid;
}
else if (x < A[mid]) {
return binarySearch(A, low, mid - 1, x);
}
else {
return binarySearch(A, mid + 1, high, x);
}
}
class Solution {
public:
int search(vector<int>& nums, int target) {
int ret = 0;
if (nums.size() == 0)
return -1;
if (nums[nums.size()/2] < target) {
vector<int> halfVec(nums.begin()+nums.size()/2+1,nums.end());
auto retIdx = search(halfVec,target);
if (retIdx == -1) return -1;
ret += retIdx + nums.size()/2+1;
} else if (nums[nums.size()/2] > target) {
vector<int> halfVec(nums.begin(),nums.begin()+nums.size()/2);
ret = search(halfVec,target);
} else {
ret = nums.size()/2;
}
return ret;
}
};# Code recursive binary search.
def binarySearchAlgorithm(arr, l, r, x):
if r >= l:
mid = l + (r - l)
if arr[mid] == x:
return mid
elif arr[mid] > x:
return binarySearch(arr, l, mid-1, x)
else:
return binarySearch(arr, mid + 1, r, x)
else:
return -1
arr = [3, 43, 56, 96]
find = 56
result = binarySearchAlgorithm(arr, 0, len(arr)-1, find)
if result != -1:
print("Element is present at index % d" % result)
else:
print("Element is not present in array")