2015 ACM-ICPC国际大学生程序设计竞赛北京赛区网络赛 1002 Mission Impossible 6

  1 #include <cstdio>
  2 #include <cstring>
  3 #include <iostream>
  4 #include <algorithm>
  5 #include <ext/rope>
  6 using namespace std;
  7 using namespace __gnu_cxx;
  8 /*
  9     鬼畜的模拟题！从新拿出来写一下还是会出错
 10     其实用rope写还是方便很多的
 11     注意一下题目的坑还是很容易过的
 12     1:每次复制文本为空，粘贴板才会清空
 13     2:当在复制状态为start时，操作D会使光标改变
 14     3:如果在文档限制长度内，不能把粘贴板上的内容复制完，则不操作
 15     4：除L，R外任何字符都能把复制状态从start转化为nothing
 16 */
 17 const int maxn = 20000;
 18 char b[maxn];
 19 int main ()
 20 {
 21     int T, n;
 22     int mark, c_state, t_state, len;
 23     scanf ("%d", &T);
 24     while (T --)
 25     {
 26         crope c, a;
 27         scanf ("%d %s", &n, b);
 28         len = strlen (b);
 29         t_state = 1;
 30         c_state = -2;
 31         mark = -1;
 32         for (int i=0; i<len; i++)
 33         {
 34             if (b[i]<=‘z‘ && b[i]>=‘a‘)
 35             {
 36                 if (c_state != -2)
 37                     c_state = -2;
 38                 if (t_state == 1 || a.size()==mark+1)
 39                 {
 40                     if (a.size() >= n)
 41                         continue;
 42                     a.insert(mark+1,b[i]);
 43                 }
 44                 else
 45                 {
 46                     a.erase (mark+1, 1);
 47                     a.insert (mark+1, b[i]);
 48 
 49                 }
 50                 mark ++;
 51             }
 52             else if (b[i] == ‘L‘)
 53             {
 54                 if (mark > -1)
 55                     mark --;
 56             }
 57             else if (b[i] == ‘R‘)
 58             {
 59                 if (a.size() > mark+1)
 60                     mark ++;
 61             }
 62             else if (b[i] == ‘S‘)
 63             {
 64                 if (c_state != -2)
 65                     c_state = -2;
 66                 t_state = (t_state + 1) % 2;
 67             }
 68             else if (b[i] == ‘D‘)
 69             {
 70                 if (c_state != -2)
 71                 {
 72                     if (mark > c_state)
 73                         a.erase (c_state + 1, mark - c_state);
 74                     if (c_state > mark)
 75                         a.erase (mark + 1, c_state - mark);
 76                     mark = min (mark, c_state);
 77                     c_state = -2;
 78                 }
 79                 else if (a.size() > mark+1)
 80                     a.erase( mark+1, 1);
 81             }
 82             else if (b[i] == ‘B‘)
 83             {
 84                 if (c_state != -2)
 85                     c_state = -2;
 86                 if (mark > -1)
 87                     a.erase (mark, 1), mark --;
 88             }
 89             else if (b[i] == ‘C‘)
 90             {
 91                 if (c_state == -2)
 92                     c_state = mark;
 93                 else
 94                 {
 95                     c = a.substr (min(c_state, mark)+1, max(c_state, mark)-min(c_state, mark));
 96                     c_state = -2;
 97                 }
 98             }
 99             else if (b[i] == ‘V‘)
100             {
101                 if (c_state != -2)
102                     c_state = -2;
103                 int mm = a.size() + c.size();
104                 if (t_state == 1 && mm > n)
105                     continue ;
106                 mm = mark + 1 + c.size();
107                 if (t_state == 0 && mm > n)
108                     continue ;
109                 mm = c.size();
110                 for (int j=0; j<mm; j++)
111                 {
112                     if (t_state == 1 || a.size()==mark+1)
113                     {
114                         if (a.size() >= n)
115                             continue;
116                         a.insert (mark+1, c.at(j));
117                     }
118                     else
119                     {
120                         a.erase (mark+1, 1);
121                         a.insert (mark+1, c.at(j));
122                     }
123                     mark ++;
124                 }
125             }
126         }
127         if (a.size() == 0)
128             printf ("NOTHING\n");
129         else
130             cout<<a<<endl;
131     }
132     return 0;
133 }
134 /*
135 3
136 5 abaaaCLLLLCDLV
137 5 abcdeSLLCLLLCRRV
138 5 abcdeCLLLCSCRRRRDV
139 
140 aaaa
141 ababc
142 abcde
143 */