Submission #292780

#	Time	Username	Problem	Language	Result	Execution time	Memory
292780		Saboon	고대 책들 (IOI17_books)	C++17	12 / 100	23 ms	32640 KiB

books

#include "books.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int maxn = 1e6 + 10;

bool visited[maxn], mark[maxn];
int c[maxn];
vector<pair<int,int>> g[maxn];
ll dp[maxn];

long long MST(int src){
    ll ret = 0;
    memset(dp, 63, sizeof dp);
    dp[src] = 0;
    set<pair<ll,int>> S;
    S.insert({dp[src],src});
    while (!S.empty()){
        int v = (*S.begin()).second;
        S.erase(S.begin());
        ret += dp[v];
        for (auto [u,w] : g[v]){
            if (dp[u] > w){
                S.erase({dp[u],u});
                dp[u] = w;
                S.insert({dp[u],u});
            }
        }
    }
    return 2LL*ret;
}

long long minimum_walk(vector<int> p, int s){
	int n = p.size();
	set<int> S;
	ll answer = 0;
    for (int i = 0; i < n; i++)
        answer += abs(p[i]-i);
	int tmp = 0, Max, Min, last;
	Max = s, last = s+1;
    for (int i = s; i < n; i++){
        if (!visited[i] and p[i] != i){
            mark[i] = 1;
            int x = i;
            c[i] = i+1;
            if (i != s and i > Max){
                g[last].push_back({c[i],i-Max});
                g[c[i]].push_back({last,0});
            }
            while (!visited[x]){
                visited[x] = 1;
                c[x] = c[i];
                if (x > Max){
                    Max = x;
                    last = c[x];
                }
                x = p[x];
            }
        }
    }
    Min = s, last = s+1;
    memset(visited, 0, sizeof visited);
	for (int i = s; i >= 0; i--){
        if (!visited[i]){
            mark[i] = 1;
            int x = i;
            if (c[i] == 0)
                c[i] = i+1;
            if (i != s and i < Min){
                g[last].push_back({c[i],Min-i});
                g[c[i]].push_back({last,0});
            }
            while (!visited[x]){
                visited[x] = 1;
                c[x] = c[i];
                if (Min > x){
                    Min = x;
                    last = c[i];
                }
                x = p[x];
            }
        }
	}
	answer += MST(s+1);
	return answer;
}

Compilation message (stderr)

books.cpp: In function 'long long int minimum_walk(std::vector<int>, int)':
books.cpp:37:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   37 |     for (int i = 0; i < n; i++)
      |     ^~~
books.cpp:39:2: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   39 |  int tmp = 0, Max, Min, last;
      |  ^~~
books.cpp:39:6: warning: unused variable 'tmp' [-Wunused-variable]
   39 |  int tmp = 0, Max, Min, last;
      |      ^~~

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