POJ1028Web Navigation

POJ1028Web Navigation

模拟题。
用一个栈记录着访问过的url，每遇到"VISIT"就将栈内当前页面（nowp指向的页面）之后的url扔掉，然后将本次访问的url入栈。

代码
 1import java.io.*;
 2import java.util.*;
 3class Main
 4{
 5    public static void main(String[] args)
 6    {
 7        String[] urlStack = new String[110];
 8        urlStack[0] = "http://www.acm.org/";
 9        int top = 1;
10        int nowp = 0;
11        Scanner sc = new Scanner(System.in);
12        String strt = sc.nextLine();
13        while(!"QUIT".equals(strt)){
14            String[] strs = strt.split(" ");
15
16            if("VISIT".equals(strs[0])){
17                System.out.println(strs[1]);
18                top = nowp + 1;
19                urlStack[top++] = strs[1];
20                nowp++;
21            }
22            else if("BACK".equals(strs[0])){
23                if(nowp > 0){
24                    System.out.println(urlStack[--nowp]);
25                }
26                else
27                    System.out.println("Ignored");
28            }
29            else if("FORWARD".equals(strs[0])){
30                if(nowp < top - 1)
31                {
32                    System.out.println(urlStack[++nowp]);
33                }
34                else
35                    System.out.println("Ignored");
36            }
37                        
38            strt = sc.nextLine();
39        }
40
41        
42    }
43    
44}
45