RosettaCodeData/Task/Superpermutation-minimisation/C++/superpermutation-minimisati...

60 lines
998 B
C++

#include <array>
#include <iostream>
#include <vector>
constexpr int MAX = 12;
static std::vector<char> sp;
static std::array<int, MAX> count;
static int pos = 0;
int factSum(int n) {
int s = 0;
int x = 0;
int f = 1;
while (x < n) {
f *= ++x;
s += f;
}
return s;
}
bool r(int n) {
if (n == 0) {
return false;
}
char c = sp[pos - n];
if (--count[n] == 0) {
count[n] = n;
if (!r(n - 1)) {
return false;
}
}
sp[pos++] = c;
return true;
}
void superPerm(int n) {
pos = n;
int len = factSum(n);
if (len > 0) {
sp.resize(len);
}
for (size_t i = 0; i <= n; i++) {
count[i] = i;
}
for (size_t i = 1; i <= n; i++) {
sp[i - 1] = '0' + i;
}
while (r(n)) {}
}
int main() {
for (size_t n = 0; n < MAX; n++) {
superPerm(n);
std::cout << "superPerm(" << n << ") len = " << sp.size() << '\n';
}
return 0;
}