Package g1301_1400.s1381_design_a_stack_with_increment_operation

Class CustomStack

java.lang.Object

g1301_1400.s1381_design_a_stack_with_increment_operation.CustomStack

public class CustomStack
extends Object

1381 - Design a Stack With Increment Operation.<p>Medium</p> <p>Design a stack which supports the following operations.</p> <p>Implement the <code>CustomStack</code> class:</p> <ul> <li><code>CustomStack(int maxSize)</code> Initializes the object with <code>maxSize</code> which is the maximum number of elements in the stack or do nothing if the stack reached the <code>maxSize</code>.</li> <li><code>void push(int x)</code> Adds <code>x</code> to the top of the stack if the stack hasn&rsquo;t reached the <code>maxSize</code>.</li> <li><code>int pop()</code> Pops and returns the top of stack or <strong>-1</strong> if the stack is empty.</li> <li><code>void inc(int k, int val)</code> Increments the bottom <code>k</code> elements of the stack by <code>val</code>. If there are less than <code>k</code> elements in the stack, just increment all the elements in the stack.</li> </ul> <p><strong>Example 1:</strong></p> <p><strong>Input</strong></p> <p>[&ldquo;CustomStack&rdquo;,&ldquo;push&rdquo;,&ldquo;push&rdquo;,&ldquo;pop&rdquo;,&ldquo;push&rdquo;,&ldquo;push&rdquo;,&ldquo;push&rdquo;,&ldquo;increment&rdquo;,&ldquo;increment&rdquo;,&ldquo;pop&rdquo;,&ldquo;pop&rdquo;,&ldquo;pop&rdquo;,&ldquo;pop&rdquo;]</p> <p>[[3],[1],[2],[],[2],[3],[4],[5,100],[2,100],[],[],[],[]]</p> <p><strong>Output:</strong> [null,null,null,2,null,null,null,null,null,103,202,201,-1]</p> <p><strong>Explanation:</strong></p> <pre><code> CustomStack customStack = new CustomStack(3); // Stack is Empty [] customStack.push(1); // stack becomes [1] customStack.push(2); // stack becomes [1, 2] customStack.pop(); // return 2 --> Return top of the stack 2, stack becomes [1] customStack.push(2); // stack becomes [1, 2] customStack.push(3); // stack becomes [1, 2, 3] customStack.push(4); // stack still [1, 2, 3], Don't add another elements as size is 4 customStack.increment(5, 100); // stack becomes [101, 102, 103] customStack.increment(2, 100); // stack becomes [201, 202, 103] customStack.pop(); // return 103 --> Return top of the stack 103, stack becomes [201, 202] customStack.pop(); // return 202 --> Return top of the stack 102, stack becomes [201] customStack.pop(); // return 201 --> Return top of the stack 101, stack becomes [] customStack.pop(); // return -1 --> Stack is empty return -1. </code></pre> <p><strong>Constraints:</strong></p> <ul> <li><code>1 <= maxSize <= 1000</code></li> <li><code>1 <= x <= 1000</code></li> <li><code>1 <= k <= 1000</code></li> <li><code>0 <= val <= 100</code></li> <li>At most <code>1000</code> calls will be made to each method of <code>increment</code>, <code>push</code> and <code>pop</code> each separately.</li> </ul>

Constructor Summary

Constructors

Constructor	Description
CustomStack(int maxSize)

Method Summary

Modifier and Type	Method	Description
void	increment(int k, int val)
int	pop()
void	push(int x)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

CustomStack

public CustomStack(int maxSize)

Method Details

push

public void push(int x)

pop

public int pop()

increment

public void increment(int k,
 int val)