import java.util.Stack;
public class GetMinStack {
private Stack<Integer> stackData=new Stack();
private Stack<Integer> stackMin=new Stack();
public void push(int newNum){
if(stackMin.isEmpty()){//若stackMin中没有数值,则将数值压入;
this.stackMin.push(newNum);
}else if(newNum<=getMin()){//若新压入的数值小于得到的最小值,则再次压入stackMin的栈顶;
this.stackMin.push(newNum);
}
this.stackData.push(newNum);//将所有的数值压入stackData;
}
public int pop(){
if(this.stackData.isEmpty()){
throw new RuntimeException("stack is empty!");
}
int value=this.stackData.pop();
if(value==this.getMin()){//同步一下,data栈已经移走了,且是最小,那么最小栈也应该移走最小的
this.stackMin.pop();
}
return value;
}
public int getMin() {
if(this.stackMin.isEmpty()){
throw new RuntimeException("stack is empty!");
}
return this.stackMin.peek();
}
public static void main(String[] args) {
GetMinStack g=new GetMinStack();
g.push(1);
g.push(3);
g.push(5);
g.push(4);
System.out.println(g.getMin());
}
}
getMin
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转载自blog.csdn.net/Answer0902/article/details/81222031
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