Submission #701814

#	Time	Username	Problem	Language	Result	Execution time	Memory
701814		Etherite	Speedrun (RMI21_speedrun)	C++17	0 / 100	180 ms	788 KiB

speedrun

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

using namespace std;

void dfsHint(int curr, int par, vector<vector<int>> &adjHint, vector<int> &path)
{
	path.push_back(curr);
	for(int i = 0; i < 10; i++) // set in big-endian
	{
		if(par & (1 << i)) setHint(curr, i + 1, 1);
		else setHint(curr, i + 1, 0);
	}
	for(int next : adjHint[curr])
	{
		if(next == par) continue;
		dfsHint(next, curr, adjHint, path);
	}
}

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());
	vector<int> path;
	dfsHint(1, 0, adjHint, path);
	for(int i = 0; i < path.size() - 1; i++)
	{
		int child = path[i + 1];
		for(int i = 10; i < 20; i++) // set in big-endian
		{
			if(child & (1 << (i - 10))) setHint(path[i], i + 1, 1);
			else setHint(path[i], i + 1, 0);
		}
	}
}

int dfs(int curr, int toTry) // returns next value to try
{
	int par = 0, child = 0;
	for(int i = 0; i < 10; i++) par += getHint(i + 1) * (1 << i);
	for(int i = 10; i < 20; i++) child += getHint(i + 1) * (1 << (i - 10));

	if(toTry == 0) toTry = child;
	if(toTry == 0) return 0;
	
	while(goTo(toTry)) 
	{
		toTry = dfs(toTry, 0);
	}
	return toTry;
}

void speedrun(int subtask, int N, int start) 
{
	if(N == 1) return;
	int l = getLength();
	int next = start, toTry = 0;
	for(int rep = 0; rep < 10000; rep++)
	{
		int par = 0;
		for(int i = 0; i < 10; i++) par += getHint(i + 1) * (1 << i);
		toTry = dfs(next, toTry);
		next = par;
	}
}

Compilation message (stderr)

speedrun.cpp: In function 'void assignHints(int, int, int*, int*)':
speedrun.cpp:33:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   33 |  for(int i = 0; i < path.size() - 1; i++)
      |                 ~~^~~~~~~~~~~~~~~~~
speedrun.cpp: In function 'void speedrun(int, int, int)':
speedrun.cpp:63:6: warning: unused variable 'l' [-Wunused-variable]
   63 |  int l = getLength();
      |      ^

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