Submission #347985

#	Time	Username	Problem	Language	Result	Execution time	Memory
347985		arnold518	Painting Walls (APIO20_paint)	C++14	100 / 100	558 ms	15724 KiB

paint

#include "paint.h"
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const int MAXN = 1e5;
const int MAXM = 5e4;
const int MAXK = 1e5;

int N, M, K;
int C[MAXN+10];
vector<int> B[MAXK+10];

int dp[2][MAXM+10], chk[MAXN+10];
int dp2[MAXN+10];

int minimumInstructions(int _N, int _M, int _K, vector<int> _C, vector<int> _A, vector<vector<int>> _B)
{
	N=_N; M=_M; K=_K;
	for(int i=0; i<N; i++) C[i]=_C[i];
	for(int i=0; i<M; i++)
	{
		for(auto it : _B[i])
		{
			B[it].push_back(i);
		}
	}

	for(int i=0; i<N; i++)
	{
		if(i>=2)
		{
			for(auto it : B[C[i-2]])
			{
				dp[i&1][it]=0;
			}
		}
		for(auto it : B[C[i]])
		{
			dp[i&1][it]=1;
			if(i!=0 && dp[i-1&1][(it+M-1)%M])
			{
				dp[i&1][it]=dp[i-1&1][(it+M-1)%M]+1;
			}
			if(dp[i&1][it]>=M)
			{
				chk[i+1]=1;
			}
		}
	}

	deque<int> DQ;
	DQ.push_back(0);
	for(int i=1; i<=N; i++)
	{
		dp2[i]=987654321;
		if(!chk[i]) continue;
		while(!DQ.empty() && DQ.front()<i-M) DQ.pop_front();
		if(DQ.empty()) continue;
		dp2[i]=dp2[DQ.front()]+1;	
		while(!DQ.empty() && dp2[DQ.back()]>=dp2[i]) DQ.pop_back();
		DQ.push_back(i);
		//printf("%d ", dp2[i]);
	}

	if(dp2[N]==987654321) return -1;
	return dp2[N];
}

Compilation message (stderr)

paint.cpp: In function 'int minimumInstructions(int, int, int, std::vector<int>, std::vector<int>, std::vector<std::vector<int> >)':
paint.cpp:44:19: warning: suggest parentheses around '-' in operand of '&' [-Wparentheses]
   44 |    if(i!=0 && dp[i-1&1][(it+M-1)%M])
      |                  ~^~
paint.cpp:46:21: warning: suggest parentheses around '-' in operand of '&' [-Wparentheses]
   46 |     dp[i&1][it]=dp[i-1&1][(it+M-1)%M]+1;
      |                    ~^~

• Subtask 1: 12 / 12
• Subtask 2: 15 / 15
• Subtask 3: 13 / 13
• Subtask 4: 23 / 23
• Subtask 5: 37 / 37