1051 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
题目分析:一道模拟题 写了半天

 #define _CRT_SECURE_NO_WARNINGS
 #include <climits>
 #include<iostream>
 #include<vector>
 #include<queue>
 #include<map>
 #include<set>
 #include<stack>
 #include<algorithm>
 #include<string>
 #include<cmath>
 using namespace std;
 stack<int> S1;

 int main()
 {
     int M, N, K;
     cin >> M >> N >> K;
     vector<int> Array(N+);
     vector<int> Test(N+);
     for (int i = ; i <= N; i++)
         Array[i] = i;
     for (int i = ; i < K; i++)
     {
         while (S1.size())
             S1.pop();
         for (int j = ; j <= N; j++)
             cin >> Test[j];
         int k = , t = ,flag=;
         while (t<=N)
         {
             if (S1.size()> M)
             {
                 flag = ;
                 break;
             }
             else if (S1.size())
             {
                 if (S1.top() == Test[t])
                 {
                     S1.pop();
                     t++;
                 }
                 else if(k<=N)
                 {
                     S1.push(Array[k]);
                     k++;
                 }
                 else
                 {
                     if (S1.top() == Test[t])
                     {
                         S1.pop();
                         t++;
                     }
                     else
                     {
                         flag = ;
                         break;
                     }
                 }
             }
             else {
                 S1.push(Array[k]);
                 k++;
             }
         }
         if (flag)
             cout << "YES" << endl;
         else
             cout << "NO" << endl;
     }
 }