Submission #701767

#	Time	Username	Problem	Language	Result	Execution time	Memory
701767		Etherite	Speedrun (RMI21_speedrun)	C++17	0 / 100	188 ms	836 KiB

speedrun

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

using namespace std;

void dfsHint(int curr, int par, vector<vector<int>> &adjHint, stack<int> &toAdd)
{
	for(int i = 9; i >= 0; i--) // set in big-endian
	{
		if(par & (1 << i)) setHint(curr, i + 1, 1);
		else setHint(curr, i + 1, 0);
	}

	for(int i = adjHint[curr].size() - 1; i >= 0; i--)
	{
		int next = adjHint[curr][i];
		if(next == par) continue;
		toAdd.push(next);
	}
	assert(!toAdd.empty());
	int second = toAdd.top();
	toAdd.pop();
	for(int i = 9; i >= 0; i--)
	{
		if(second & (1 << i)) setHint(curr, i + 11, 1);
		else setHint(curr, i + 11, 0);
	}

	for(int next : adjHint[curr])
	{
		if(next == par) continue;
		dfsHint(next, curr, adjHint, toAdd);
	}
}

void assignHints(int subtask, int N, int A[], int B[]) 
{
	setHintLen(20);
	vector<vector<int>> adjHint(N + 1);
	for(int i = 1; i < N; i++)
	{
		adjHint[A[i]].push_back(B[i]);
		adjHint[B[i]].push_back(A[i]);
	}
	for(int i = 1; i <= N; i++) sort(adjHint[i].begin(), adjHint[i].end());
	stack<int> toAdd;
	dfsHint(1, 0, adjHint, toAdd);
}

int dfsSpeedrun(int curr, int par, vector<int> &vis)
{
	int child = 0;
	for(int i = 10; i < 20; i++) child += getHint(i + 1) * (1 << (i - 10));

	while(1)
	{
		bool canDescend = goTo(child);
		if(canDescend)
		{
			child = dfsSpeedrun(child, curr, vis);
		}
		else return child;
	}
}

void speedrun(int subtask, int N, int start) 
{
	int l = getLength();
	
	int par = 0;
	for(int i = 0; i < 10; i++) par += getHint(i + 1) * (1 << i);

	vector<int> vis(N + 1);
	vis[start] = 1;
	dfsSpeedrun(start, par, vis);
}

Compilation message (stderr)

speedrun.cpp: In function 'void speedrun(int, int, int)':
speedrun.cpp:68:6: warning: unused variable 'l' [-Wunused-variable]
   68 |  int l = getLength();
      |      ^

• Subtask 1: 0 / 21
• Subtask 2: 0 / 8
• Subtask 3: 0 / 19
• Subtask 4: 0 / 12
• Subtask 5: 0 / 40