Submission #423468

#	Time	Username	Problem	Language	Result	Execution time	Memory
423468		Theo830	Ancient Books (IOI17_books)	C++17	0 / 100	1 ms	332 KiB

books

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll INF = 1e9;
ll MOD = 998244353;
typedef pair<ll,ll> ii;
#define iii pair<int,int>
#define f(i,a,b) for(ll i = a;i < b;i++)
#define pb push_back
#define vll vector<ll>
#define F first
#define S second
#define all(x) (x).begin(), (x).end()
///I hope I will get uprating and don't make mistakes
///I will never stop programming
///sqrt(-1) Love C++
///Please don't hack me
///@TheofanisOrfanou Theo830
///Think different approaches (bs,dp,greedy,graphs,shortest paths,mst)
///Stay Calm
///Look for special cases
///Beware of overflow and array bounds
///Think the problem backwards
///Training
#include "books.h"
long long minimum_walk(std::vector<int> p, int s) {
    ll ans = 0;
    ll n = p.size();
    assert(s == 0 && n <= 1000);
    bool v[n] = {0};
    ll dist = 0;
    ll l[n],r[n];
    f(i,0,n){
        l[i] = -1;
    }
    vector<ii>rang;
    f(i,0,n){
        if(p[i] != i && !v[i]){
            ll last = i;
            ll st = i;
            ll pos = p[i];
            v[i] = 1;
            l[st] = i,r[st] = pos;
            while(pos != st){
                l[st] = min(l[st],pos);
                r[st] = max(r[st],pos);
                v[pos] = 1;
                ans += abs(pos - last);
                last = pos;
                pos = p[pos];
            }
            ans += abs(pos - last);
            l[st] = min(l[st],pos);
            r[st] = max(r[st],pos);
            rang.pb(ii(l[st],r[st]));
        }
        else{
            v[i] = 1;
        }
    }
    sort(all(rang));
    if(!rang.empty()){
        dist = rang[0].F;
    }
    f(i,0,rang.size()-1){
        if(rang[i].S < rang[i+1].F){
            dist = rang[i+1].F;
        }
    }
    ans += 2 * dist;
    return ans;
}
/*
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;
}
*/
/*
4 0
0 2 3 1
*/

Compilation message (stderr)

books.cpp: In function 'long long int minimum_walk(std::vector<int>, int)':
books.cpp:8:33: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    8 | #define f(i,a,b) for(ll i = a;i < b;i++)
......
   65 |     f(i,0,rang.size()-1){
      |       ~~~~~~~~~~~~~~~~~          
books.cpp:65:5: note: in expansion of macro 'f'
   65 |     f(i,0,rang.size()-1){
      |     ^

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