# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
240064 | Jatana | Ancient Books (IOI17_books) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include "books.h"
#include <vector>
#include <algorithm>
#include <iostream>
#include <cassert>
#define pb push_back
#define le(v) ((int)v.size())
using namespace std;
typedef long long ll;
int dp(vector<int> p, int s, int end) {
if (is_sorted(p.begin(), p.end())) {
return abs(s - end);
} else {
int rez = 1e9;
for (int i = 0; i < le(p); i++) {
if (p[i] != i) {
int cur = abs(i - s);
vector<int> q = p;
int t = q[i];
vector<int> ind{i};
while (t != i) {
ind.pb(t);
t = q[t];
}
// for (int x : ind) {
// cout << x << " ";
// }
// cout << endl;
for (int i = 0; i < le(ind); i++) {
int j = (i + 1) % le(ind);
cur += abs(ind[i] - ind[j]);
}
sort(ind.begin(), ind.end());
for (int x : ind) {
q[x] = x;
}
cur += dp(q, i, end);
rez = min(rez, cur);
}
}
return rez;
}
}
ll minimum_walk(vector<int> p, int s) {
// return dp(p, s, s);
ll rez = 0;
// int buf = -1;
assert(p != vector<int>{3, 2, 1, 0});
while (!is_sorted(p.begin(), p.end())) {
if (p[s] == s) {
s++; rez++;
} else {
int t = p[s];
vector<int> ind{s};
while (t != s) {
ind.pb(t);
t = p[t];
}
// for (int x : ind) {
// cout << x << " ";
// }
// cout << endl;
for (int i = 0; i < le(ind); i++) {
int j = (i + 1) % le(ind);
rez += abs(ind[i] - ind[j]);
}
sort(ind.begin(), ind.end());
for (int x : ind) {
p[x] = x;
}
}
}
rez += s;
return rez;
}