Submission #20590

#	Time	Username	Problem	Language	Result	Execution time	Memory
20590		model_code	Martian DNA (IOI16_dna)	C++14	100 / 100	13 ms	2024 KiB

dna

#include "dna.h"

#include <cstdlib>

std::string zeroes(int m) {
    std::string res = "";
    for (int i = 0; i < m; ++i)
        res += '0';
    return res;
}

std::string analyse(int n, int t) {

    int l = 0, r = n + 1;
    while (l < r - 1) {
        int m = (l + r) >> 1;
        if (make_test(zeroes(m)))
            l = m;
        else
            r = m;
    }

    std::string s = zeroes(l);
    int zeroesCount = 0;
    int maxZeroesCount = l;
    while (true) {
        s += '1';
        if (!make_test(s)) {
            s[s.size() - 1] = '0';
            ++zeroesCount;
        } else {
            zeroesCount = 0;
        }
        if (zeroesCount + maxZeroesCount >= n || zeroesCount >= maxZeroesCount + 1)
            break;
    }
    
    l = 0, r = zeroesCount;
    s = s.substr(0, s.size() - zeroesCount);

    while (l < r - 1) {
        int m = (l + r) >> 1;
        if (make_test(s + zeroes(m)))
            l = m;
        else
            r = m;
    }

    s = s + zeroes(l);

    while (s.size() < n) {
        s = "1" + s;
        if (!make_test(s)) {
            s[0] = '0';
        }
    }

    return s;
}

Compilation message (stderr)

dna.cpp: In function 'std::__cxx11::string analyse(int, int)':
dna.cpp:51:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     while (s.size() < n) {
                     ^
grader.cpp: In function 'bool make_test(std::__cxx11::string)':
grader.cpp:14:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < p.size(); i++) {
                    ^
grader.cpp:23:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 1; i <= ss.size(); i++) {
                    ^
grader.cpp:28:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if (pr[i] == p.size()) {
             ^

• Subtask 1: 11 / 11
• Subtask 2: 25 / 25
• Subtask 3: 64 / 64