Submission #824961

#	Time	Username	Problem	Language	Result	Execution time	Memory
824961		kwongweng	Ancient Books (IOI17_books)	C++17	0 / 100	0 ms	212 KiB

books

#include "books.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> ii;
typedef vector<ii> vii;
typedef long double ld;
typedef pair<ll, ll> pll;
#define FOR(i, a, b) for(int i = a; i < b; i++)
#define ROF(i, a, b) for(int i = a; i >= b; i--)
#define ms memset
#define pb push_back
#define fi first
#define se second

ll minimum_walk(vi p, int s) {
	int n=p.size();
	vi used(n);
	vii r; ll ans=0;
	FOR(i,0,n){
		if (used[i] || p[i]==i) continue;
		int cur=i; int mx=0;
		while (p[cur] != i){
			ans += abs(p[cur]-cur);
			mx=max(mx,cur); used[cur]=1; cur=p[cur];
		}
		ans += abs(i-cur); mx=max(mx,cur); used[cur]=1;
		r.pb({i,mx});
	}
	if (r.empty()) return ans;
	int len=r.size(); bool sol=true; if (p[s]!=s) sol=false;
	if (r[0].fi>s) {ans += 2*(r[0].fi-s); sol=false;}
	int mx=r[0].fi;
	FOR(i,0,len){
		if (r[i].fi > mx) {
			ans += 2*(r[i].fi-mx);
			if (r[i].fi > s && s > mx) sol=false;
		}
		mx=max(mx,r[i].se);
	}
	if (s>mx) {ans += 2*(s-mx); sol=false;}
	//if (!sol) return ans;
	int L=s,R=s;
	while (p[L]==L) L--;
	while (p[R]==R) R++;
	ans += 2*min(s-L,R-s);
	return ans;
}

Compilation message (stderr)

books.cpp: In function 'll minimum_walk(vi, int)':
books.cpp:32:25: warning: variable 'sol' set but not used [-Wunused-but-set-variable]
   32 |  int len=r.size(); bool sol=true; if (p[s]!=s) sol=false;
      |                         ^~~

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