111 lines
3.6 KiB
Java
111 lines
3.6 KiB
Java
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//请你设计一个支持下述操作的栈。
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//
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// 实现自定义栈类 CustomStack ：
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//
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//
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// CustomStack(int maxSize)：用 maxSize 初始化对象，maxSize 是栈中最多能容纳的元素数量，栈在增长到 maxSize
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//之后则不支持 push 操作。
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// void push(int x)：如果栈还未增长到 maxSize ，就将 x 添加到栈顶。
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// int pop()：弹出栈顶元素，并返回栈顶的值，或栈为空时返回 -1 。
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// void inc(int k, int val)：栈底的 k 个元素的值都增加 val 。如果栈中元素总数小于 k ，则栈中的所有元素都增加 val 。
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//
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//
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//
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//
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//
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// 示例：
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//
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// 输入：
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//["CustomStack","push","push","pop","push","push","push","increment","increment
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//","pop","pop","pop","pop"]
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//[[3],[1],[2],[],[2],[3],[4],[5,100],[2,100],[],[],[],[]]
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//输出：
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//[null,null,null,2,null,null,null,null,null,103,202,201,-1]
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//解释：
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//CustomStack customStack = new CustomStack(3); // 栈是空的 []
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//customStack.push(1); // 栈变为 [1]
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//customStack.push(2); // 栈变为 [1, 2]
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//customStack.pop(); // 返回 2 --> 返回栈顶值 2，栈变为 [1]
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//customStack.push(2); // 栈变为 [1, 2]
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//customStack.push(3); // 栈变为 [1, 2, 3]
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//customStack.push(4); // 栈仍然是 [1, 2, 3]，不能添加其他元素使栈大小变为
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// 4
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//customStack.increment(5, 100); // 栈变为 [101, 102, 103]
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//customStack.increment(2, 100); // 栈变为 [201, 202, 103]
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//customStack.pop(); // 返回 103 --> 返回栈顶值 103，栈变为 [201
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//, 202]
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//customStack.pop(); // 返回 202 --> 返回栈顶值 202，栈变为 [201
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//]
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//customStack.pop(); // 返回 201 --> 返回栈顶值 201，栈变为 []
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//customStack.pop(); // 返回 -1 --> 栈为空，返回 -1
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//
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//
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//
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//
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// 提示：
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//
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//
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// 1 <= maxSize <= 1000
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// 1 <= x <= 1000
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// 1 <= k <= 1000
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// 0 <= val <= 100
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// 每种方法 increment，push 以及 pop 分别最多调用 1000 次
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//
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// Related Topics 栈 设计
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// 👍 47 👎 0
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package leetcode.editor.cn;
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//1381:设计一个支持增量操作的栈
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public class DesignAStackWithIncrementOperation {
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public static void main(String[] args) {
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//测试代码
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// Solution solution = new DesignAStackWithIncrementOperation().new Solution();
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}
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//力扣代码
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//leetcode submit region begin(Prohibit modification and deletion)
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class CustomStack {
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int[] stack;
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int index;
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public CustomStack(int maxSize) {
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stack = new int[maxSize];
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index = 0;
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}
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public void push(int x) {
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if (index < stack.length) {
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stack[index] = x;
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index++;
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}
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}
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public int pop() {
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if(index==0){
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return -1;
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}
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index--;
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int num = stack[index];
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stack[index] = 0;
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return num;
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}
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public void increment(int k, int val) {
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int size = Math.min(index, k);
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for (int i = 0; i < size; i++) {
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stack[i] += val;
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}
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}
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}
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/**
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* Your CustomStack object will be instantiated and called as such:
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* CustomStack obj = new CustomStack(maxSize);
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* obj.push(x);
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* int param_2 = obj.pop();
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* obj.increment(k,val);
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*/
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//leetcode submit region end(Prohibit modification and deletion)
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}
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