package Stack;

import java.io.*;

public class infixApp {
	public static void main(String[] args) throws IOException {
		String input,output;
		while(true) {
			System.out.println("输入:");
			System.out.flush();
			input = getString();
			if(input.equals(""))
				break;
			
			IntoPost theTrans = new IntoPost(input);
			output = theTrans.doTrans();
			
			System.out.print("Postfix is"+output+"\n");
			
		}
	}
	
	public static String getString() throws IOException{
		InputStreamReader isr = new InputStreamReader(System.in);
		BufferedReader br = new BufferedReader(isr);
		
		String s = br.readLine();
		return s;
		
	}
}

class IntoPost{
	private Stack stack;
	private String input;
	private String output="";
	
	public IntoPost(String in) {
		this.input = in;
		int stackSize = this.input.length();
		this.stack = new Stack(stackSize);
	}
	
	public String doTrans() {
		for(int i=0;i<this.input.length();i++) {
			char ch = this.input.charAt(i);
			this.stack.display("For "+ch+" ");
			switch(ch) {
				case '+':
				case '-':
					this.gotOper(ch,1);
					break;
				case '*':
				case '/':
					this.gotOper(ch,2);
					break;
				case '(':
					this.stack.push(ch);
					break;
				case ')':
					this.gotParen(ch);
					break;
				default:
					this.output = output + ch;
					break;
			}
			
		}
		
		while(!this.stack.isEmpty()) {
			this.stack.display("While ");
			this.output = this.output + this.stack.pop();
		}
		
		this.stack.display("End ");
		return this.output;
	}
	
	public void gotOper(char opThis, int prec1) {
		while(!this.stack.isEmpty()) {
			char opTop = this.stack.pop();
			if(opTop=='(') {
				this.stack.push(opTop);
				break;
			}else {
				int prec2;
				if(opTop=='+' || opTop=='-') {
					prec2 = 1;
				}else {
					prec2 = 2;
				}
				
				if(prec2 < prec1) {
					this.stack.push(opTop);
					break;
				}else {
					this.output = this.output+opTop;
				}
				
			}
		}
		this.stack.push(opThis);
	}
	
	public void gotParen(char ch) {
		while(!this.stack.isEmpty()) {
			char chx = this.stack.pop();
			if(chx =='(') {
				break;
			}else {
				this.output = this.output+chx;
			}
		}
	}
}

class Stack {
	private char[] a;
	private int maxsize;
	private int top;
	
	public Stack(int s) {
		this.maxsize = s;
		this.a = new char[this.maxsize];
		this.top = -1;
	}
	
	//入栈
	public void push(char value) {
		this.a[++this.top] = value;
	}
	
	//出栈
	public char pop() {
		return this.a[this.top--];
	}
	
	//查看
	public char peek() {
		return this.a[this.top];
	}
	
	public char peekN(int n) {
		return this.a[n];
	}
	
	//是否为空
	public boolean isEmpty() {
		return (this.top == -1);
	}
	
	//是否已满
	public boolean isFull() {
		return (this.top == this.maxsize-1);
	}
	
	public int size() {
		return this.top-1;
	}
	
	public void display(String s) {
		System.out.println(s);
		System.out.println("Stack (bottom->top)");
		for(int j=0;j<this.size();j++) {
			System.out.print(this.peekN(j));
			System.out.print("");
		}
		
	}
}