-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathMinStack.java
More file actions
50 lines (41 loc) · 1.02 KB
/
MinStack.java
File metadata and controls
50 lines (41 loc) · 1.02 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
package leetcode.easy.page1;
import java.util.Arrays;
/**
* @author Kyle
* @create 2018/8/23 1:32
*/
public class MinStack {
private int maxCapacity = 256;
private int minNumIndex;
private int minNumStack[];
private int index;
private int[] stack;
public MinStack() {
minNumIndex = -1;
minNumStack = new int[maxCapacity];
index = -1;
stack = new int[maxCapacity];
}
public void push(int x) {
if(index + 1 >= maxCapacity) {
maxCapacity *= 2;
stack = Arrays.copyOf(stack, maxCapacity);
minNumStack = Arrays.copyOf(minNumStack, maxCapacity);
}
stack[++index] = x;
if(minNumIndex == -1 || x <= getMin()) {
minNumStack[++minNumIndex] = x;
}
}
public void pop() {
if(stack[index--] == getMin()) {
minNumIndex--;
}
}
public int top() {
return stack[index];
}
public int getMin() {
return minNumStack[minNumIndex];
}
}