Given a stack which can keep M numbers at most. Push N numbers in the order of 1, 2, 3, ..., N and pop randomly. You are supposed to tell if a given sequence of numbers is a possible pop sequence of the stack. For example, if M is 5 and N is 7, we can obtain 1, 2, 3, 4, 5, 6, 7 from the stack, but not 3, 2, 1, 7, 5, 6, 4.ios
Input Specification:dom
Each input file contains one test case. For each case, the first line contains 3 numbers (all no more than 1000): M (the maximum capacity of the stack), N (the length of push sequence), and K (the number of pop sequences to be checked). Then K lines follow, each contains a pop sequence of N numbers. All the numbers in a line are separated by a space.spa
Output Specification:code
For each pop sequence, print in one line "YES" if it is indeed a possible pop sequence of the stack, or "NO" if not.blog
Sample Input:ci
5 7 5 1 2 3 4 5 6 7 3 2 1 7 5 6 4 7 6 5 4 3 2 1 5 6 4 3 7 2 1 1 7 6 5 4 3 2
Sample Output:input
YES NO NO YES NO
C++代码以下：it
1 #include<iostream> 2 #include<stack> 3 #include<queue> 4 using namespace std; 5 6 int main() { 7 int m, n, k; 8 cin >> m >> n >> k; 9 while (k--) { 10 int temp; 11 stack<int>s; 12 queue<int>q; 13 for (int i = 0; i < n; i++) { 14 cin >> temp; 15 q.push(temp); 16 } 17 for (int i = 1; i <= n;i++) { 18 s.push(i); 19 if (s.size() > m) break; 20 while (!s.empty() && ( q.front() == s.top() ) ) { 21 q.pop(); 22 s.pop(); 23 if (q.empty()) break; 24 } 25 } 26 if (q.empty()) cout << "YES" << endl; 27 else cout << "NO" << endl; 28 } 29 return 0; 30 }