sicily/1509. Rails

 1 #include <iostream>
 2 #include <stack>
 3 using namespace std;
 4 int train[1001];
 5 int main()
 6 {
 7         int t;
 8         int fs=0;
 9         while(cin>>t&&t!=0)
10         {
11                 while(cin>>train[0]&&train[0]!=0)
12                 {
13                         for(int i=1;i<t;i++)
14                         {
15                                 cin>>train[i];
16                         }
17                         stack<int> s;
18                         int k=0;
19                         for(int i=1;i<=t;i++)
20                         {
21                                 //从A到来的车与目标序列相同，让A车过
22                                 if(i==train[k])
23                                         k++;
24                                 else
25                                 {
26                                         //如果栈中的车与目标队列相同，那么就是让队列中的车出来
27                                         while(!s.empty()&&s.top()==train[k])
28                                         {
29                                                 s.pop();
30                                                 k++;
31                                         }
32                                         
33                                         s.push(i);
34                                 }
35                         }
36                         //最后清空堆栈
37                         while(!s.empty())
38                         {
39                                 if(s.top()==train[k])
40                                         k++;
41                                 s.pop();
42                         }
43                         if(k==t)
44                                 cout<<"Yes"<<endl;
45                         else
46                                 cout<<"No"<<endl;
47                         
48                 }
49                 cout<<endl;
50         }
51 }