7-3 Pop Sequence (25分)
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.

Input Specification:
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.

Output Specification:
For each pop sequence, print in one line “YES” if it is indeed a possible pop sequence of the stack, or “NO” if not.

Sample Input:
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:
YES
NO
NO
YES
NO

#include<iostream>
#include<vector>
using namespace std;
#define MAX 1000int main()
{vector<int>stack;stack.reserve(MAX);int m,n,k,i,j;cin>>m>>n>>k;int seq[n];while(k--){for(i=0;i<n;i++){cin>>seq[i];}j=0;stack.clear();for(i=1;i<=n;i++){stack.push_back(i);if(stack.size()>m) break;while(stack.size()!=0&&stack.back()==seq[j]){stack.pop_back();j++;}}if(stack.size()==0) cout<<"YES"<<endl;else cout<<"NO"<<endl;}return 0;
}