Submission #423930

#	Time	Username	Problem	Language	Result	Execution time	Memory
423930		Abelyan	Ancient Books (IOI17_books)	C++17	50 / 100	249 ms	21188 KiB

books

#ifndef ALEXPC
#include "books.h"
#endif

#include <bits/stdc++.h>
using namespace std;

#define FOR(i,n) for (int i=0;i<(n);++i)
#define FORT(i,a,b) for (int i=(a);i<=(b);++i)
#define FORD(i,n) for (int i=(n)-1;i>=0;--i)
#define FORTD(i,a,b) for (int i=(a);i>=(b);--i)
#define trav(to,v) for (auto to : v)
#define all(v) v.begin(),v.end()
#define fr first
#define sc second

typedef long long ll;

const int N = 1e6+6;


long long minimum_walk(vector<int> p, int s) {
	ll ans=0;
	bool bl=false;
	vector<pair<int,int> > vc;
	FOR(i,p.size()){
		ans+=llabs(p[i]-i);
		if (p[i]!=i || i==s)bl=true;
		if (bl)vc.push_back({min(i,p[i]),max(i,p[i])});
	}
	while(vc.size() && vc.back().fr==vc.back().sc && vc.back().fr!=s)vc.pop_back();
	sort(all(vc));
	int mx=-1;
	FOR(i,vc.size()){
		if (i && vc[i].fr>mx){
			ans+=2;
		}
		if (vc[i].sc>mx)mx=vc[i].sc;
	}
	return ans;
}


#ifdef ALEXPC

#include <cstdio>
#include <vector>
#include <cassert>

using namespace std;

int main() {
	int n, s;
	assert(2 == scanf("%d %d", &n, &s));

	vector<int> p((unsigned) n);
	for(int i = 0; i < n; i++)
		assert(1 == scanf("%d", &p[(unsigned) i]));

	long long res = minimum_walk(p, s);
	printf("%lld\n", res);

	return 0;
}


#endif

Compilation message (stderr)

books.cpp: In function 'long long int minimum_walk(std::vector<int>, int)':
books.cpp:8:32: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    8 | #define FOR(i,n) for (int i=0;i<(n);++i)
      |                                ^
books.cpp:26:2: note: in expansion of macro 'FOR'
   26 |  FOR(i,p.size()){
      |  ^~~
books.cpp:8:32: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    8 | #define FOR(i,n) for (int i=0;i<(n);++i)
      |                                ^
books.cpp:34:2: note: in expansion of macro 'FOR'
   34 |  FOR(i,vc.size()){
      |  ^~~

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