Submission #934276

#	Time	Username	Problem	Language	Result	Execution time	Memory
934276		GrindMachine	Ancient Books (IOI17_books)	C++17	50 / 100	107 ms	33468 KiB

books

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) (int)a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x,y) ((x+y-1)/(y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a,b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a,b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif

/*

refs:
edi

*/

const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

#include "books.h"

ll minimum_walk(std::vector<int> a, int s) {
    while(!a.empty() and a.back()+1 == sz(a)){
        a.pop_back();
    }
    if(a.empty()) return 0;

    ll n = sz(a);
    ll lb = 0;
    rep(i,n) lb += abs(i-a[i]);
        
    vector<bool> vis(n);
    vector<pll> b;

    rep(i,n){
        if(vis[i]) conts;
        ll j = i;
        ll l = inf2, r = -inf2;
        while(!vis[j]){
            vis[j] = 1;
            amin(l,j);
            amax(r,j);
            j = a[j];
        }

        b.pb({l,r});
    }

    sort(all(b));
    ll mx_reach = -1;
    ll segs = 0;

    for(auto [l,r] : b){
        if(l > mx_reach){
            segs++;
        }
        amax(mx_reach,r);
    }

    ll ans = lb+2*(segs-1);
    return ans;
}

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