LeetCode155. ๆๅฐๆ ๐๐๐๐๐ไธญ็ญ
้ฎ้ขๆ่ฟฐ
ๅๆ้พๆฅ๏ผ155. ๆๅฐๆ
่ฎพ่ฎกไธไธชๆฏๆ push ๏ผpop ๏ผtop ๆไฝ๏ผๅนถ่ฝๅจๅธธๆฐๆถ้ดๅ
ๆฃ็ดขๅฐๆๅฐๅ
็ด ็ๆ ใ
ๅฎ็ฐ MinStack ็ฑป:
MinStack()ๅๅงๅๅ ๆ ๅฏน่ฑกใvoid push(int val)ๅฐๅ ็ด valๆจๅ ฅๅ ๆ ใvoid pop()ๅ ้คๅ ๆ ้กถ้จ็ๅ ็ด ใint top()่ทๅๅ ๆ ้กถ้จ็ๅ ็ด ใint getMin()่ทๅๅ ๆ ไธญ็ๆๅฐๅ ็ด ใ
็คบไพ 1:
่พๅ
ฅ๏ผ
["MinStack","push","push","push","getMin","pop","top","getMin"]
[[],[-2],[0],[-3],[],[],[],[]]
่พๅบ๏ผ
[null,null,null,null,-3,null,0,-2]
่งฃ้๏ผ
MinStack minStack = new MinStack();
minStack.push(-2);
minStack.push(0);
minStack.push(-3);
minStack.getMin(); --> ่ฟๅ -3.
minStack.pop();
minStack.top(); --> ่ฟๅ 0.
minStack.getMin(); --> ่ฟๅ -2.
ๆ็คบ๏ผ
-231 <= val <= 231 - 1popใtopๅgetMinๆไฝๆปๆฏๅจ้็ฉบๆ ไธ่ฐ็จpush,pop,top, andgetMinๆๅค่ขซ่ฐ็จ3 * 104ๆฌก
ไปฃ็ ๅฎ็ฐ
Java
class MinStack {
Stack<Integer> stack1;
Stack<Integer> stack2;
public MinStack() {
stack1 = new Stack();
stack2 = new Stack();
}
public void push(int val) {
stack1.push(val);
if(stack2.isEmpty() || stack2.peek() >= val){
stack2.push(val);
}
}
public void pop() {
if(stack1.peek().intValue() == stack2.peek().intValue()){
stack2.pop();
}
stack1.pop();
}
public int top() {
return stack1.peek();
}
public int getMin() {
return stack2.peek();
}
}
/**
* Your MinStack object will be instantiated and called as such:
* MinStack obj = new MinStack();
* obj.push(val);
* obj.pop();
* int param_3 = obj.top();
* int param_4 = obj.getMin();
*/
Python
class MinStack(object):
def __init__(self):
self.stack1 = []
self.stack2 = []
def push(self, val):
"""
:type val: int
:rtype: None
"""
self.stack1.append(val)
if not self.stack2 or self.stack2[-1] >= val:
self.stack2.append(val)
def pop(self):
"""
:rtype: None
"""
if self.stack1[-1] == self.stack2[-1]:
self.stack2.pop()
self.stack1.pop()
def top(self):
"""
:rtype: int
"""
return self.stack1[-1]
def getMin(self):
"""
:rtype: int
"""
return self.stack2[-1]
C++
class MinStack {
public:
stack<int> stack1;
stack<int> stack2;
MinStack() {
}
void push(int val) {
stack1.push(val);
if(stack2.empty() || stack2.top() >= val){
stack2.push(val);
}
}
void pop() {
if(stack1.top() == stack2.top()){
stack2.pop();
}
stack1.pop();
}
int top() {
return stack1.top();
}
int getMin() {
return stack2.top();
}
};
Go
type MinStack struct {
stack1 []int
stack2 []int
}
func Constructor() MinStack {
return MinStack{[]int{}, []int{}}
}
func (this *MinStack) Push(val int) {
this.stack1 = append(this.stack1, val)
if len(this.stack2) == 0 || this.stack2[len(this.stack2)-1] >= val {
this.stack2 = append(this.stack2, val)
}
}
func (this *MinStack) Pop() {
if this.stack1[len(this.stack1)-1] == this.stack2[len(this.stack2)-1] {
this.stack2 = this.stack2[:len(this.stack2)-1]
}
this.stack1 = this.stack1[:len(this.stack1)-1]
}
func (this *MinStack) Top() int {
return this.stack1[len(this.stack1)-1]
}
func (this *MinStack) GetMin() int {
return this.stack2[len(this.stack2)-1]
}