剑指 Offer 30. 包含min函数的栈
2021-08-12 本文已影响0人
上杉丶零
class MinStack {
private Stack<Integer> aStack;
private Stack<Integer> bStack;
public MinStack() {
aStack = new Stack<>();
bStack = new Stack<>();
}
public void push(int x) {
aStack.push(x);
if (bStack.empty() || bStack.peek() >= x) {
bStack.push(x);
}
}
public void pop() {
if (aStack.pop().equals(bStack.peek())) {
bStack.pop();
}
}
public int top() {
return aStack.peek();
}
public int min() {
return bStack.peek();
}
}
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