UVA 12538 Version Controlled IDE
ext/rope 真是持久化字符串处理神器......
详见: http://www.sgi.com/tech/stl/Rope.html
| UVA - 12538
Version
Controlled IDE
|
12538 Version Controlled IDE
Programmers use version control systems to manage les in their projects, but in these systems, versions
are saved only when you manually submit. Can you implement an IDE that automatically saves a new
version whenever you insert or delete a string?
Positions in the bu er are numbered from 1 from left to right. Initially, the bu er is empty and in
version 0. Then you can execute 3 commands (vnow means the version before executing the command,
and L[v] means the length of bu er at version v):
1 p s: insert string s after position p (0 p L[vnow], p = 0 means insert before the start of the
bu er). s contains at most 1 and at most 100 letters.
2 p c: remove c characters starting at position p (p 1; p + c L[vnow] + 1). The remaining
charactesr (if any) will be shifted left, lling the blank
3 v p c: print c characters starting at position p (p 1; p + c L[v] + 1), in version v (1 v
vnow).
The rst command is guaranteed to be command 1(insert). After executing each command 1 or 2,
version is incremented by 1.
Input
There is only one test case. It begins with a single integer n (1 n 50; 000), the number of commands.
Each of the following n lines contains a command. The total length of all inserted string will not
exceed 1,000,000.
Output
Print the results of command 3, in order. The total length of all printed strings will not exceed 200,000.
Obfuscation:
In order to prevent you from preprocessing the command, we adopt the following obfuscation scheme:
Each type-1 command becomes 1 p + d s
Each type-2 command becomes 2 p + d c + d
Each type-3 command becomes 3 v + d p + d c + d
Where d is the number of lowercase letter `c' you printed, before processing this command.
Before the obfuscation, the sample input would be:
6
1 0 abcdefgh
2 4 3
3 1 2 5
3 2 2 3
1 2 xy
3 3 2 4
This is the real input that your program must process when it reads the Sample Input
below.Universidad de Valladolid OJ: 12538 { Version Controlled IDE 2/2
Sample Input
6
1 0 abcdefgh
2 4 3
3 1 2 5
3 3 3 4
1 4 xy
3 5 4 6
Sample Output
bcdef
bcg
bxyc
#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <ext/rope>
using namespace std;
using namespace __gnu_cxx;
const int maxn=50500;
crope tmp,var[maxn],t;
int n,op,p,c,v,d,curv;
char str[maxn];
int main()
{
while(scanf("%d",&n)!=EOF)
{
curv=0;d=0;
while(n--)
{
scanf("%d",&op);
if(op==1)
{
scanf("%d%s",&p,str);
p-=d;
t.insert(p,str);
var[++curv]=t;
}
else if(op==2)
{
scanf("%d%d",&p,&c);
p-=d;c-=d;
t.erase(p-1,c);
var[++curv]=t;
}
else if(op==3)
{
scanf("%d%d%d",&v,&p,&c);
v-=d;p-=d;c-=d;
tmp=var[v].substr(p-1,c);
d+=count(tmp.begin(),tmp.end(),'c');
cout<<tmp<<endl;
}
}
}
return 0;
}