제출 #970791

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
970791		12345678	Rainforest Jumps (APIO21_jumps)	C++17	23 / 100	738 ms	119400 KiB

jumps

#include "jumps.h"
#include <bits/stdc++.h>

using namespace std;

const int nx=2e5+5, kx=18;

int l[nx], r[nx], deg[nx], lvl[nx], p[kx][nx], pa[nx][kx], in[nx], out[nx], rt, t;
vector<int> d[nx], g[nx];

void dfs(int u, int p)
{
    //cout<<"dfs "<<u<<'\n';
    in[u]=++t;
    pa[u][0]=p;
    for (int i=1; i<kx; i++) pa[u][i]=pa[pa[u][i-1]][i-1];
    for (auto v:g[u]) dfs(v, u);
    out[u]=t;
}

void init(int N, std::vector<int> H) {
    stack<int> s;
    for (int i=0; i<N; i++) l[i]=r[i]=N;
    for (int i=0; i<N; i++)
    {
        while (!s.empty()&&H[s.top()]<H[i]) s.pop();
        if (!s.empty()) l[i]=s.top(), d[s.top()].push_back(i), deg[i]++;
        s.push(i);
    }
    while (!s.empty()) s.pop();
    for (int i=N-1; i>=0; i--)
    {
        while (!s.empty()&&H[s.top()]<H[i]) s.pop();
        if (!s.empty()) r[i]=s.top(), d[s.top()].push_back(i), deg[i]++;
        s.push(i);
    }
    queue<int> q;
    for (int i=0; i<N; i++) if (l[i]==N&&r[i]==N) q.push(i), rt=i;
    while (!q.empty())
    {
        auto u=q.front();
        q.pop();
        for (auto x:d[u]) if (--deg[x]==0) q.push(x);
        lvl[u]=max(lvl[l[u]], lvl[r[u]])+1;
    }
    for (int i=0; i<N; i++)
    {
        if (lvl[l[i]]>lvl[r[i]]) g[l[i]].push_back(i);
        else g[r[i]].push_back(i);
    }
    for (int i=0; i<kx; i++) p[i][N]=N;
    for (int i=0; i<N; i++) p[0][i]=(lvl[l[i]]<lvl[r[i]])?l[i]:r[i];
    for (int i=1; i<kx; i++) for (int j=0; j<N; j++) p[i][j]=p[i-1][p[i-1][j]];
    dfs(rt, rt);
}

int minimum_jumps(int A, int B, int C, int D) {
    if (A!=B) cout<<1/0;
    int tmp=A;
    for (int i=kx-1; i>=0; i--) if (A<=pa[tmp][i]&&pa[tmp][i]<=B) tmp=pa[tmp][i];
    A=tmp;
    if (!(in[D]<=in[A]&&out[A]<=out[D])) return -1;
    int res=0;
    for (int i=kx-1; i>=0; i--) if (lvl[p[i][A]]>=lvl[D]) res+=(1<<i), A=p[i][A];
    return res+lvl[A]-lvl[D];
}

/*
7 6
3 2 1 6 4 5 7
1 2 5 5
1 2 6 6
0 3 6 6
1 4 6 6
2 3 4 4
4 5 6 6

*/

컴파일 시 표준 에러 (stderr) 메시지

jumps.cpp: In function 'int minimum_jumps(int, int, int, int)':
jumps.cpp:58:22: warning: division by zero [-Wdiv-by-zero]
   58 |     if (A!=B) cout<<1/0;
      |                     ~^~

• Subtask 1: 0 / 4
• Subtask 2: 0 / 8
• Subtask 3: 0 / 13
• Subtask 4: 0 / 12
• Subtask 5: 23 / 23
• Subtask 6: 0 / 21
• Subtask 7: 0 / 19