// Calculates bijective variant of BWT using sais_bwt
std::string bwt (std::string x)
{
const unsigned char* T = reinterpret_cast <const unsigned char*> (x.c_str());
unsigned char* U = (unsigned char*) malloc(sizeof(unsigned char) * x.length());
int* A = (int*) malloc(sizeof(int) * x.length());
sais_bwt (T, U, A, x.length());
std::string transform (reinterpret_cast <char*> (U));
return transform;
}
void bwt_transform(char* string, char* result, int len) {
int i;
int* A = (int*)malloc(len * sizeof(int));
int eof_pos = sais_bwt(string, result, A, len);
assert(eof_pos > 0);
char eof = result[0];
for (i = 0; i < eof_pos - 1; i++) {
result[i] = result[i+1];
}
result[eof_pos - 1] = eof;
result[len] = 0;
free(A);
}
