Submission #286389

#	Time	Username	Problem	Language	Result	Execution time	Memory
286389		Kastanda	Highway design (CEOI12_highway)	C++11	100 / 100	1 ms	768 KiB

highway

// M
#include<bits/stdc++.h>
#include "office.h"
using namespace std;
const int N = 100005;
int main()
{
        int n = GetN();

        if (isOnLine(1, 2, 3))
        {
                vector < int > vec;
                for (int i = 4; i + 1 <= n && (int)vec.size() <= 1; i += 2)
                        if (!isOnLine(1, i, i + 1))
                                vec.push_back(i);
                if ((int)vec.size() == 2)
                {
                        int a = vec[0] + (int)isOnLine(1, 2, vec[0]);
                        int b = vec[1] + (int)isOnLine(1, 2, vec[1]);
                        Answer(1, 2, a, b);
                        return 0;
                }
                assert((int)vec.size());
                if (n % 2 == 1)
                {
                        Answer(1, 2, vec[0], vec[0] + 1);
                        return 0;
                }
                if (isOnLine(1, 2, vec[0]))
                {
                        Answer(1, 2, vec[0] + 1, n);
                        return 0;
                }
                if (isOnLine(1, 2, vec[0] + 1))
                {
                        Answer(1, 2, vec[0], n);
                        return 0;
                }
                Answer(1, 2, vec[0], vec[0] + 1);
                return 0;
        }
        int traitor = -1;
        if (isOnLine(1, 2, 4))
                traitor = 3;
        else if (isOnLine(1, 3, 4))
                traitor = 2;
        else if (isOnLine(2, 3, 4))
                traitor = 1;

        if (traitor == -1)
        {
                for (int i = 1; i <= 4; i ++)
                        for (int j = i + 1; j <= 4; j ++)
                                if (isOnLine(i, j, 5))
                                {
                                        int a = 1;
                                        while (a == i || a == j)
                                                a ++;
                                        int b = a + 1;
                                        while (b == i || b == j)
                                                b ++;
                                        Answer(i, j, a, b);
                                        return 0;
                                }
        }

        int good_samaritan_1 = (traitor == 1) ? 2 : 1;
        int good_samaritan_2 = (traitor <= 2) ? 3 : 2;
        vector < int > vec;
        for (int i = 5; i + 1 <= n && !(int)vec.size(); i += 2)
                if (!isOnLine(good_samaritan_1, i, i + 1))
                        vec.push_back(i);
        if (!(int)vec.size())
        {
                assert(n % 2 == 1);
                Answer(good_samaritan_1, good_samaritan_2, traitor, n);
                return 0;
        }
        if (isOnLine(good_samaritan_1, good_samaritan_2, vec[0]))
                Answer(good_samaritan_1, good_samaritan_2, traitor, vec[0] + 1);
        else
                Answer(good_samaritan_1, good_samaritan_2, traitor, vec[0]);
        return 0;
}

Compilation message (stderr)

office.c: In function 'int isOnLine(int, int, int)':
office.c:85:13: warning: ISO C++ forbids converting a string constant to 'char*' [-Wwrite-strings]
   85 |     _Fin(0, "Protocol error");
      |             ^~~~~~~~~~~~~~~~
office.c:88:13: warning: ISO C++ forbids converting a string constant to 'char*' [-Wwrite-strings]
   88 |     _Fin(0, "Protocol error");
      |             ^~~~~~~~~~~~~~~~
office.c:92:17: warning: ISO C++ forbids converting a string constant to 'char*' [-Wwrite-strings]
   92 |     _Fin(false, "Too many questions");
      |                 ^~~~~~~~~~~~~~~~~~~~
office.c:83:7: warning: unused variable 'i' [-Wunused-variable]
   83 |   int i;
      |       ^
office.c: In function 'void Answer(int, int, int, int)':
office.c:123:13: warning: ISO C++ forbids converting a string constant to 'char*' [-Wwrite-strings]
  123 |     _Fin(0, "Protocol error");
      |             ^~~~~~~~~~~~~~~~
office.c:128:44: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
  128 |       if( (-_Apa[na1]==_N-3) && (na2!=na1) && (nb2!=na1) ||
      |           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~
office.c:130:21: warning: ISO C++ forbids converting a string constant to 'char*' [-Wwrite-strings]
  130 |          _Fin(true, "Correct");
      |                     ^~~~~~~~~
office.c:132:22: warning: ISO C++ forbids converting a string constant to 'char*' [-Wwrite-strings]
  132 |          _Fin(false, "Wrong answer");
      |                      ^~~~~~~~~~~~~~
office.c:134:44: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
  134 |       if( (-_Apa[na2]==_N-3) && (na1!=na2) && (nb1!=na2) ||
      |           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~
office.c:136:21: warning: ISO C++ forbids converting a string constant to 'char*' [-Wwrite-strings]
  136 |          _Fin(true, "Correct");
      |                     ^~~~~~~~~
office.c:138:22: warning: ISO C++ forbids converting a string constant to 'char*' [-Wwrite-strings]
  138 |          _Fin(false, "Wrong answer");
      |                      ^~~~~~~~~~~~~~
office.c:140:19: warning: ISO C++ forbids converting a string constant to 'char*' [-Wwrite-strings]
  140 |       _Fin(false, "Wrong answer");
      |                   ^~~~~~~~~~~~~~
office.c:142:14: warning: ISO C++ forbids converting a string constant to 'char*' [-Wwrite-strings]
  142 |   _Fin(true, "Correct");
      |              ^~~~~~~~~
office.c:120:27: warning: unused variable 'pont' [-Wunused-variable]
  120 |   int na1, nb1, na2, nb2, pont;
      |                           ^~~~
office.c: In function 'void _doInit()':
office.c:33:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   33 |     scanf("%d", &_N);
      |     ~~~~~^~~~~~~~~~~

• Subtask 1: 100 / 100