paths.hpp
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#ifndef SASS_PATHS_H
#define SASS_PATHS_H
#include <string>
#include <vector>
#include <sstream>
template<typename T>
std::string vector_to_string(std::vector<T> v)
{
std::stringstream buffer;
buffer << "[";
if (!v.empty())
{ buffer << v[0]; }
else
{ buffer << "]"; }
if (v.size() == 1)
{ buffer << "]"; }
else
{
for (size_t i = 1, S = v.size(); i < S; ++i) buffer << ", " << v[i];
buffer << "]";
}
return buffer.str();
}
namespace Sass {
template<typename T>
std::vector<std::vector<T> > paths(std::vector<std::vector<T> > strata, size_t from_end = 0)
{
if (strata.empty()) {
return std::vector<std::vector<T> >();
}
size_t end = strata.size() - from_end;
if (end <= 1) {
std::vector<std::vector<T> > starting_points;
starting_points.reserve(strata[0].size());
for (size_t i = 0, S = strata[0].size(); i < S; ++i) {
std::vector<T> starting_point;
starting_point.push_back(strata[0][i]);
starting_points.push_back(starting_point);
}
return starting_points;
}
std::vector<std::vector<T> > up_to_here = paths(strata, from_end + 1);
std::vector<T> here = strata[end-1];
std::vector<std::vector<T> > branches;
branches.reserve(up_to_here.size() * here.size());
for (size_t i = 0, S1 = up_to_here.size(); i < S1; ++i) {
for (size_t j = 0, S2 = here.size(); j < S2; ++j) {
std::vector<T> branch = up_to_here[i];
branch.push_back(here[j]);
branches.push_back(branch);
}
}
return branches;
}
}
#endif