13af6ab5fSopenharmony_ci/*
23af6ab5fSopenharmony_ci * Copyright (c) 2024 Huawei Device Co., Ltd.
33af6ab5fSopenharmony_ci * Licensed under the Apache License, Version 2.0 (the "License");
43af6ab5fSopenharmony_ci * you may not use this file except in compliance with the License.
53af6ab5fSopenharmony_ci * You may obtain a copy of the License at
63af6ab5fSopenharmony_ci *
73af6ab5fSopenharmony_ci * http://www.apache.org/licenses/LICENSE-2.0
83af6ab5fSopenharmony_ci *
93af6ab5fSopenharmony_ci * Unless required by applicable law or agreed to in writing, software
103af6ab5fSopenharmony_ci * distributed under the License is distributed on an "AS IS" BASIS,
113af6ab5fSopenharmony_ci * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
123af6ab5fSopenharmony_ci * See the License for the specific language governing permissions and
133af6ab5fSopenharmony_ci * limitations under the License.
143af6ab5fSopenharmony_ci */
153af6ab5fSopenharmony_ci
163af6ab5fSopenharmony_ciinterface MyStack<Item> {
173af6ab5fSopenharmony_ci    getTop() : Item|null;
183af6ab5fSopenharmony_ci    pop() : Item|null;
193af6ab5fSopenharmony_ci    push(item : Item) : void;
203af6ab5fSopenharmony_ci    isEmpty() : boolean;
213af6ab5fSopenharmony_ci    size() : int;
223af6ab5fSopenharmony_ci}
233af6ab5fSopenharmony_ci
243af6ab5fSopenharmony_ciclass MyArrayStack<Item> implements MyStack<Item> {
253af6ab5fSopenharmony_ci
263af6ab5fSopenharmony_ci    private container : Item[];
273af6ab5fSopenharmony_ci    private top : int = -1;
283af6ab5fSopenharmony_ci    private readonly DEFAULT_SIZE : int = 100;
293af6ab5fSopenharmony_ci
303af6ab5fSopenharmony_ci    constructor() {
313af6ab5fSopenharmony_ci        this.container = new Item[this.DEFAULT_SIZE];
323af6ab5fSopenharmony_ci        this.top = -1;
333af6ab5fSopenharmony_ci    }
343af6ab5fSopenharmony_ci
353af6ab5fSopenharmony_ci    constructor(size: int) {
363af6ab5fSopenharmony_ci        this.container = new Item[size];
373af6ab5fSopenharmony_ci    }
383af6ab5fSopenharmony_ci
393af6ab5fSopenharmony_ci    override getTop() : Item|null {
403af6ab5fSopenharmony_ci        if (this.top == -1) {
413af6ab5fSopenharmony_ci            return null;
423af6ab5fSopenharmony_ci        }
433af6ab5fSopenharmony_ci        return this.container[this.top];
443af6ab5fSopenharmony_ci    }
453af6ab5fSopenharmony_ci
463af6ab5fSopenharmony_ci    override pop() : Item|null {
473af6ab5fSopenharmony_ci        if (this.top == -1) {
483af6ab5fSopenharmony_ci            return null;
493af6ab5fSopenharmony_ci        }
503af6ab5fSopenharmony_ci        return this.container[this.top--];
513af6ab5fSopenharmony_ci    }
523af6ab5fSopenharmony_ci
533af6ab5fSopenharmony_ci    override push(item : Item) : void {
543af6ab5fSopenharmony_ci        this.container[++this.top] = item;
553af6ab5fSopenharmony_ci    }
563af6ab5fSopenharmony_ci
573af6ab5fSopenharmony_ci    override isEmpty() : boolean {
583af6ab5fSopenharmony_ci        return (this.top == -1);
593af6ab5fSopenharmony_ci    }
603af6ab5fSopenharmony_ci
613af6ab5fSopenharmony_ci    override size() : int {
623af6ab5fSopenharmony_ci        return (this.top + 1);
633af6ab5fSopenharmony_ci    }
643af6ab5fSopenharmony_ci}
653af6ab5fSopenharmony_ci
663af6ab5fSopenharmony_cifunction main() : void {
673af6ab5fSopenharmony_ci  let stack1 : MyArrayStack<Int>;
683af6ab5fSopenharmony_ci  stack1 = new MyArrayStack<Int>();
693af6ab5fSopenharmony_ci  assert(stack1.isEmpty() == true);
703af6ab5fSopenharmony_ci  assert(stack1.size() == 0);
713af6ab5fSopenharmony_ci
723af6ab5fSopenharmony_ci  stack1.push(new Int(10));
733af6ab5fSopenharmony_ci  assert(stack1.isEmpty() == false);
743af6ab5fSopenharmony_ci  assert(stack1.size() == 1);
753af6ab5fSopenharmony_ci  assert((stack1.getTop() as Int) == 10);
763af6ab5fSopenharmony_ci
773af6ab5fSopenharmony_ci  stack1.push(new Int(20));
783af6ab5fSopenharmony_ci  stack1.push(new Int(30));
793af6ab5fSopenharmony_ci  assert(stack1.isEmpty() == false);
803af6ab5fSopenharmony_ci  assert(stack1.size() == 3);
813af6ab5fSopenharmony_ci  assert((stack1.getTop() as Int) == 30);
823af6ab5fSopenharmony_ci
833af6ab5fSopenharmony_ci  assert((stack1.pop() as Int) == 30);
843af6ab5fSopenharmony_ci  assert(stack1.size() == 2);
853af6ab5fSopenharmony_ci  assert((stack1.pop() as Int) == 20);
863af6ab5fSopenharmony_ci  assert(stack1.size() == 1);
873af6ab5fSopenharmony_ci  assert((stack1.pop() as Int) == 10);
883af6ab5fSopenharmony_ci  assert(stack1.size() == 0);
893af6ab5fSopenharmony_ci  assert(stack1.isEmpty() == true);
903af6ab5fSopenharmony_ci
913af6ab5fSopenharmony_ci  assert(stack1.getTop() == null);
923af6ab5fSopenharmony_ci  assert(stack1.pop() == null);
933af6ab5fSopenharmony_ci  assert(stack1.size() == 0);
943af6ab5fSopenharmony_ci  assert(stack1.isEmpty() == true);
953af6ab5fSopenharmony_ci
963af6ab5fSopenharmony_ci}
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