Submission #45212

#	Time	Username	Problem	Language	Result	Execution time	Memory
45212		reality	Hidden Sequence (info1cup18_hidden)	C++17	100 / 100	6 ms	640 KiB

hidden

#include "grader.h"
#include "bits/stdc++.h"
using namespace std;
#define fi first
#define se second
#define ll long long
#define dbg(v) cerr<<#v<<" = "<<v<<'\n'
#define vi vector<int>
#define vl vector <ll>
#define pii pair<int,int>
#define mp make_pair
#define db long double
#define pb push_back
#define all(s) s.begin(),s.end()
template < class T > T smin(T &a,T b) {if (a > b) a = b;return a;}
template < class T > T smax(T &a,T b) {if (a < b) a = b;return a;}

int get(string str) {
	vi cnt;
	for (auto it : str)
		cnt.pb(it - '0');
	return isSubsequence(cnt);
}

vector < int > findSequence (int N) {
    const int lim = (N / 2) + 1;
    string str = "";
    int w = 1;
    while (str.length() < lim && get(str + "0")) str += "0";
    if (str.length() == lim) {
    	w = 0;
    	str = "";
    	while (get(str + "1"))
    		str += "1";
    }
    vector < string > S[2];
    S[0].pb("");
    S[1].pb("");
    for (int i = 1;i <= N;++i)
    	S[0].pb(S[0].back() + "0"),S[1].pb(S[1].back() + "1");
    const int SZ = str.length();
    string answer = "";
    int l = 0,r = N - SZ;
    for (int i = 0;i <= SZ;++i) {
		int ok = 1;
		while (ok && r > 0) {
			if (SZ - i + l <= i + r) {
				if (get(S[w][l + 1] + S[w^1][SZ - i]))
					answer += w + '0',++l,--r;
				else 
					ok = 0;
			} else {
				if (!get(S[w^1][i + 1] + S[w][r]))
					answer += w + '0',++l,--r;
				else 
					ok = 0;
			}
    	}
    	if (i != SZ)
    		answer += (1 - w) + '0';
    }
    vi ans;
    for (auto it : answer)
    	ans.pb(it - '0');
    return ans;
}

Compilation message (stderr)

hidden.cpp: In function 'std::vector<int> findSequence(int)':
hidden.cpp:29:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     while (str.length() < lim && get(str + "0")) str += "0";
            ~~~~~~~~~~~~~^~~~~
hidden.cpp:30:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     if (str.length() == lim) {
         ~~~~~~~~~~~~~^~~~~~
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