Submission #790893

#	Time	Username	Problem	Language	Result	Execution time	Memory
790893		NothingXD	Ancient Books (IOI17_books)	C++17	50 / 100	136 ms	16436 KiB

books

#include "books.h"
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef complex<ld> point;

void debug_out(){cerr << endl;}

template<typename Head, typename... Tail>
void debug_out(Head H, Tail... T){
	cerr << H << ' ';
	debug_out(T...);
}

#define debug(...) cerr << "(" << #__VA_ARGS__ << "): ", debug_out(__VA_ARGS__)
#define F first
#define S second
#define all(x) x.begin(), x.end()
#define MP(x, y) make_pair(x, y)

const int maxn = 1e6 + 10;
const ll inf = 1e18;
int n, mn, mx, cnt[maxn][2];

ll Calc(){
	ll ans = 0;
	for (int i = mn+1; i <= mx; i++){
		cnt[i][0] += cnt[i-1][0];
		cnt[i][1] += cnt[i-1][1];
		//debug(i, cnt[i][0], cnt[i][1]);
		if (cnt[i][0] == 0){
			cnt[i][0]++;
			cnt[i+1][0]--;
		}
		if (cnt[i][1] == 0){
			cnt[i][1]++;
			cnt[i+1][1]--;
		}
		//debug(i, cnt[i][0], cnt[i][1]);
		ans += 2 * max(cnt[i][0], cnt[i][1]);
	}
	return ans;
}

ll minimum_walk(vector<int> p, int s) {
	n = p.size();
	mn = s, mx = s;
	int mxmn = -1, mnmx = n+1;
	for (int i = 0; i < n; i++){
		if (p[i] == i) continue;
		mn = min(mn, i);
		if (i <= s) mxmn = max(mxmn, i);
		mx = max(mx, i);
		if (s <= i) mnmx = min(mnmx, i);
		if (p[i] < i){
			cnt[p[i]+1][0]++;
			cnt[i+1][0]--;
		}
		else{
			cnt[i+1][1]++;
			cnt[p[i]+1][1]--;
		}
	}
	//debug(mn, mx);
	if (mn == mx) return 0;
	//debug(1);
	if (mxmn == -1) mxmn = s;
	if (mnmx == n+1) mnmx = s;
	//debug(mxmn, mnmx);
	ll ans = inf;
	for (int j = 0; j < 4; j++){
		memset(cnt, 0, sizeof cnt);
		if (j == 0){
			cnt[mxmn+1][0]++;
			cnt[mxmn+1][1]++;
			cnt[s+1][0]--;
			cnt[s+1][1]--;
		}
		else if (j == 1){
			cnt[mnmx+1][0]--;
			cnt[mnmx+1][1]--;
			cnt[s+1][0]++;
			cnt[s+1][1]++;
		}
		else if (j == 2){
			cnt[mxmn+1][1]++;
			cnt[s+1][1]--;
			cnt[s+1][1]++;
			cnt[mnmx+1][1]--;
		}
		else{
			cnt[mxmn+1][0]++;
			cnt[s+1][0]--;
			cnt[s+1][0]++;
			cnt[mnmx+1][0]--;
		}
		for (int i = 0; i < n; i++){
			if (p[i] == i) continue;
			if (p[i] < i){
				cnt[p[i]+1][0]++;
				cnt[i+1][0]--;
			}
			else{
				cnt[i+1][1]++;
				cnt[p[i]+1][1]--;
			}
		}
		ans = min(ans, Calc());
	}

	return ans;
}

• Subtask 1: 12 / 12
• Subtask 2: 10 / 10
• Subtask 3: 28 / 28
• Subtask 4: 0 / 20
• Subtask 5: 0 / 30