/**
*  @license
* Copyright 2021, JsData. All rights reserved.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.

* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
* ==========================================================================
*/
/**
 * A variant of a binary max-heap with a size limit.
 * If more elements than the size limit are added,
 * only the smallest encountered elements are retained.
 * This data structure is used in k-nearest-neighbor
 * searches to retain the k nearest results during
 * tree traversal.
 */
export declare class CappedMaxHeap {
    _keys: Float32Array;
    _vals: Int32Array;
    /**
     * Index of the currently first entry.
     * The entries are added from right to
     * left until `_pos = 0`, at which point
     * adding further elements results in
     * replacement.
     */
    _pos: number;
    /**
     * Creates a new heap using the given key
     * and value array as underlying data storage.
     * The heap will modify these arrays directly.
     *
     * @param keys Key array to be used by the heap.
     * @param vals Value array to be used by the heap.
     */
    constructor(keys: Float32Array, vals: Int32Array);
    /**
     * Returns the currently larges key without removing it.
     */
    get maxKey(): number;
    /**
     * Adds an entry to this heap. If, after adding,
     * the size limit is exceeded, the largest entry
     * is removed as well, even the entry that was
     * just added if it has the largest key.
     *
     * @param key Key of the added entry.
     * @param val Value of the added entry.
     */
    add(key: number, val: number): void;
    /**
     * Sorts the entries of this heap by their keys in ascending
     * order. This method destroys the heap property and should
     * only be called after all elements have been added.
     */
    sort(): void;
}