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重构

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This commit is contained in:
邹晓航
2015-01-12 13:30:33 +08:00
parent b77522e253
commit 7adeaab4f9
1 changed files with 60 additions and 62 deletions
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58
TinySTL/SuffixArray.h
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@@ -2,7 +2,6 @@
#define _SUFFIX_ARRAY_H_
#include <vector>
#include <memory>
namespace TinySTL{
@@ -26,20 +25,12 @@ namespace TinySTL{
calHeight(arr, len);
}
array_type suffixArray(){
return _suffix_array;
}
array_type heightArray(){
return _height_array;
}
array_type rankArray(){
return _rank_array;
}
array_type suffixArray()const{ return _suffix_array; }
array_type heightArray()const{ return _height_array; }
array_type rankArray()const{ return _rank_array; }
private:
template<class InputIteraotr>
bool cmp(const InputIteraotr arr, size_t a, size_t b, size_t l){
return arr[a] == arr[b] && arr[a + l] == arr[b + l];
}
bool cmp(const InputIteraotr arr, size_t a, size_t b, size_t l);
void calRank(){
_rank_array.resize(_suffix_array.size());
for (auto i = 0; i != _suffix_array.size(); ++i){
@@ -47,7 +38,29 @@ namespace TinySTL{
}
}
template<class InputIterator>
void calSuffix(const InputIterator arr, size_t len, size_t max_len){
void calSuffix(const InputIterator arr, size_t len, size_t max_len);
template<class InputIteraotr>
void calHeight(const InputIteraotr arr, size_t len);
};
template<class InputIteraotr>
bool suffix_array::cmp(const InputIteraotr arr, size_t a, size_t b, size_t l){
return arr[a] == arr[b] && arr[a + l] == arr[b + l];
}
template<class InputIteraotr>
void suffix_array::calHeight(const InputIteraotr arr, size_t len){
_height_array.resize(_suffix_array.size() - 1);
for (auto i = 0; i != _suffix_array.size() - 1; ++i){
auto n = 0;
for (auto j = _suffix_array[i], k = _suffix_array[i + 1];
arr[j] == arr[k] && (arr + j) != (arr + len) && (arr + k) != (arr + len);
++j, ++k)
++n;
_height_array[i] = n;
}
}
template<class InputIterator>
void suffix_array::calSuffix(const InputIterator arr, size_t len, size_t max_len){
//采用了罗穗骞论文中实现的倍增算法
//算法时间复杂度 = O(nlg(n))
_suffix_array.resize(len);
@@ -65,8 +78,7 @@ namespace TinySTL{
//下面这层循环中p代表rank值不用的字符串的数量，如果p达到len，那么各个字符串的大小关系就已经明了了。
//j代表当前待合并的字符串的长度，每次将两个长度为j的字符串合并成一个长度为2*j的字符串，当然如果包含字符串末尾具体则数值应另当别论，但思想是一样的。
//max_len同样代表基数排序的元素的取值范围
for (j = 1, p = 1; p < len; j *= 2, max_len = p)
{
for (j = 1, p = 1; p < len; j *= 2, max_len = p){
//以下两行代码实现了对第二关键字的排序
for (p = 0, i = len - j; i < len; i++) y[p++] = i;
for (i = 0; i < len; i++) if (_suffix_array[i] >= j) y[p++] = _suffix_array[i] - j;
@@ -84,20 +96,6 @@ namespace TinySTL{
x[_suffix_array[i]] = cmp(y, _suffix_array[i - 1], _suffix_array[i], j) ? p - 1 : p++;
}
}
template<class InputIteraotr>
void calHeight(const InputIteraotr arr, size_t len)
{
_height_array.resize(_suffix_array.size() - 1);
for (auto i = 0; i != _suffix_array.size() - 1; ++i){
auto n = 0;
for (auto j = _suffix_array[i], k = _suffix_array[i + 1];
arr[j] == arr[k] && (arr + j) != (arr + len) && (arr + k) != (arr + len);
++j, ++k)
++n;
_height_array[i] = n;
}
}
};
}
#endif