| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 248925 | kostia244 | 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"
#pragma GCC optimize("O2,unroll-loops")
#pragma GCC target("avx,avx2,sse,sse2,ssse3")
#include<bits/extc++.h>
using namespace std;
const int maxn = 1<<20;
using ll = long long;
using namespace __gnu_pbds;
using oset = tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>;
ll vis[maxn][4];
ll minimum_walk(vector<int> p, int s) {
oset pref, suf;
vector<int> pos(p.size());
ll ans = 0, lst = -1, fi = -1;
for(int i = 0; i < p.size(); i++) suf.insert(i), pos[p[i]] = i;
for(int t, i = 0; i < p.size(); i++) {
//cout << i << "::\n";
int v = p[i];
suf.erase(v);
if(i != v) {
vis[i][(v > i)*3]++;
vis[i][1 + (pos[i]>i)]++;
}
t = pref.size()-pref.order_of_key(i+1);
vis[i][1] += t, vis[i][3] += t;
t = suf.order_of_key(i);
vis[i][0] += t, vis[i][2] += t;
pref.insert(v);
if(vis[i][0] + vis[i][2] + vis[i][3] + vis[i][1]) {
lst = i;
if(fi == -1) fi = i;
}
//for(int j = 0; j < 4; j++) cout << vis[i][j] << " "; cout << endl;
if(i) {
assert(vis[i][0] == vis[i-1][2]);
assert(vis[i][1] == vis[i-1][3]);
}
}
fi = min(fi, s);
for(int i = fi; i <= lst; i++) {
for(int j = 0; j < 4; j++) {
if(i == lst && j >= 2) break;
if(i == fi && j < 2) continue;
if(vis[i][j] == 0) {
vis[i][j]++;
vis[i + (j<2?-1:1)][j^3]++;
}
}
}
for(int i = 0; i < p.size(); i++) {
//cout << vis[i][0] << " " << vis[i][1] << " " << vis[i][2] << " " << vis[i][3] << " " << g[i] << endl;
vis[i][2] = vis[i][3] = max(vis[i][2], vis[i][3]);
vis[i][0] = vis[i][1] = max(vis[i][0], vis[i][1]);
ans += (vis[i][0] + vis[i][2]);
}
return ans;
}