Submission #96625

#	Time	Username	Problem	Language	Result	Execution time	Memory
96625		KLPP	Hidden Sequence (info1cup18_hidden)	C++14	100 / 100	183 ms	504 KiB

hidden

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

using namespace std;
vector<int> query;
bool q(int first, int a, int b){query.clear();
	for(int i=0;i<a;i++)query.push_back(first);
	for(int i=0;i<b;i++)query.push_back(1-first);
	return isSubsequence(query);
}
vector < int > findSequence (int N)
{
	int zeros,ones;
	zeros=-1;
	ones=-1;
	for(int i=1;i<=N/2+1;i++){
		vector<int> query(i);
		for(int j=0;j<i;j++)query[j]=0;
		if(!isSubsequence(query)){
			zeros=i-1;
			i=N/2+1;
		}
	}
	if(zeros!=-1)ones=N-zeros;
	for(int i=1;i<=N/2+1;i++){
		vector<int> query(i);
		for(int j=0;j<i;j++)query[j]=1;
		if(!isSubsequence(query)){
			ones=i-1;
			i=N/2+1;
		}
	}
	if(ones!=-1)zeros=N-ones;
	vector<int> ans;
	if(zeros==0){
		for(int i=0;i<N;i++)ans.push_back(1);
		return ans;
	}
	if(ones==0){
		for(int i=0;i<N;i++)ans.push_back(0);
		return ans;
	}
	vector<int> query;
	int obj=0;
	if(zeros>=ones){
		obj=1;
		swap(ones,zeros);
	}
	int maxLength=N/2+1;
	//cout<<obj<<" "<<zeros<<" "<<ones<<endl;
	int seq[zeros+1];
	for(int i=1;i<=zeros;i++){
		int k=zeros+1-i;
		int m1,m2;
		for(int j=0;i+j<=maxLength;j++){
			if(q(obj,i,j))m1=j;
		}
		for(int j=0;k+j<=maxLength;j++){
			if(q(1-obj,j,k))m2=j;
		}
		if(m1+i==maxLength){
			m1=ones-m2;
		}else{
			m2=ones-m1;
		}
		//cout<<m1<<" A "<<m2<<endl;
		seq[i-1]=m2;
	}
	seq[zeros]=ones;
	for(int i=0;i<=zeros;i++){
		if(i!=0){
			for(int j=0;j<seq[i]-seq[i-1];j++)ans.push_back(1-obj);
		}else{
			for(int j=0;j<seq[i];j++)ans.push_back(1-obj);
		}
		if(i!=zeros)ans.push_back(obj);
	}
	return ans;
}

Compilation message (stderr)

hidden.cpp: In function 'std::vector<int> findSequence(int)':
hidden.cpp:62:6: warning: 'm2' may be used uninitialized in this function [-Wmaybe-uninitialized]
    m1=ones-m2;
    ~~^~~~~~~~
hidden.cpp:64:6: warning: 'm1' may be used uninitialized in this function [-Wmaybe-uninitialized]
    m2=ones-m1;
    ~~^~~~~~~~
grader.cpp: In function 'int main()':
grader.cpp:28:43: warning: format '%d' expects argument of type 'int', but argument 3 has type 'std::vector<int>::size_type {aka long unsigned int}' [-Wformat=]
     fprintf (fifo_out, "%d\n", ans.size ());
                                ~~~~~~~~~~~^
grader.cpp:29:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i=0; i<ans.size () && i < N; i++)
                   ~^~~~~~~~~~~~

• Subtask 1: 20 / 20
• Subtask 2: 80 / 80