Submission #790926

#	Time	Username	Problem	Language	Result	Execution time	Memory
790926		NothingXD	Ancient Books (IOI17_books)	C++17	50 / 100	101 ms	17916 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];
bool mark[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]--;
			mark[i][0] = true;
		}
		if (cnt[i][1] == 0){
			cnt[i][1]++;
			cnt[i+1][1]--;
			mark[i][1] = true;
		}
		if (cnt[i][0] < cnt[i][1]){
			mark[i][0] = true;
		}
		if (cnt[i][0] > cnt[i][1]){
			mark[i][1] = true;
		}
		//debug(i, cnt[i][0], cnt[i][1]);
		ans += 2 * max(cnt[i][0], cnt[i][1]);
	}
	debug(ans);
	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 = Calc();
	int cnt1 = 0, cnt2 = 0;
	for (int i = mxmn+1; i <= s; i++){
		cnt1 += (!mark[i][0]);
		cnt1 += (!mark[i][1]);
	}
	for (int i = s+1; i <= mnmx; i++){
		cnt2 += (!mark[i][0]);
		cnt2 += (!mark[i][1]);
	}
	return ans + 2 * min(s - mxmn, mnmx - s);
}

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