Submission #395075

#	Time	Username	Problem	Language	Result	Execution time	Memory
395075		Nicholas_Patrick	Cop and Robber (BOI14_coprobber)	C++17	100 / 100	879 ms	5120 KiB

coprobber

#include "coprobber.h"
// #include "grader.cpp"
#include <cstdio>
#include <queue>
#include <bitset>
#include <algorithm>
using namespace std;

int cop;
bool a[MAX_N][MAX_N];
vector<int> adjLis[MAX_N];
//sub2
int sidelength;
vector<vector<int>> solved, cnt;
vector<bitset<500>> done;
void solve(int cop, int robber, bool copturn=true){
	//calling this function: robber caught
	if(copturn){
		if(done[cop][robber])
			return;
		done[cop][robber]=true;
		for(int i: adjLis[robber]){
			cnt[cop][i]--;
			if(cnt[cop][i]==0)//no place to run
				solve(cop, i, false);
		}
	}else{
		for(int i: adjLis[cop]){
			if(solved[i][robber]==-1){
				solved[i][robber]=cop;
				solve(i, robber, true);
			}
		}
		if(solved[cop][robber]==-1){
			solved[cop][robber]=cop;
			solve(cop, robber, true);
		}
	}
}
int start(int n, bool A[MAX_N][MAX_N]){
	for(int i=n; i--;)for(int j=n; j--;)
		a[i][j]=A[i][j];
	for(int i=n; i--;)for(int j=n; j--;){
		if(a[i][j])
			adjLis[i].push_back(j);
	}
	solved.assign(n, vector<int>(n, -1));
	cnt.assign(n, vector<int>(n));
	done.resize(n);
	for(int i=n; i--;)for(int j=n; j--;)
		cnt[i][j]=adjLis[j].size();

	for(int i=n; i--;){
		solved[i][i]=i;
		solve(i, i);
	}
	for(int i=n; i--;)for(int j: adjLis[i]){
		solved[i][j]=j;
		solve(i, j);
	}
	if(*min_element(solved[0].begin(), solved[0].end())>=0)
		return cop=0;
	return -1;
}
int nextMove(int r){
	return cop=solved[cop][r];
}

• Subtask 1: 16 / 16
• Subtask 2: 14 / 14
• Subtask 3: 30 / 30
• Subtask 4: 40 / 40