#include "longesttrip.h"
#include <bits/stdc++.h>
using namespace std;
vector<int> longest_trip(int n, int d)
{
vector<int> c[2];
c[0] = {0};
for (int i = 1; i < n; i++)
{
int x = c[0].back();
if (are_connected({i}, {x})) c[0].push_back(i);
else c[1].push_back(i);
}
if (size(c[1]) > size(c[0]))
swap(c[0], c[1]);
if (empty(c[1]))
return c[0];
if (!are_connected(c[0], c[1]))
return c[0];
for (int u : {0, 1})
{
int v = u ^ 1;
int x = c[v][0];
if (are_connected({x}, {c[u][0]}))
{
reverse(begin(c[u]), end(c[u]));
for (int y : c[v])
c[u].push_back(y);
return c[u];
}
if (are_connected({x}, {c[u].back()}))
{
for (int y : c[v])
c[u].push_back(y);
return c[u];
}
}
// both c[0] and c[1] are cycles
int low = 0, high = size(c[0]);
while (high - low > 1)
{
int mid = (low + high) / 2;
if (are_connected(vector<int>(begin(c[0]) + low, begin(c[0]) + mid), c[1])) high = mid;
else low = mid;
}
int id0 = low;
low = 0, high = size(c[1]);
while (high - low > 1)
{
int mid = (low + high) / 2;
if (are_connected(vector<int>(begin(c[1]) + low, begin(c[1]) + mid), {x})) high = mid;
else low = mid;
}
int id1 = low;
if (id0 < size(c[0]) - 1)
rotate(begin(c[0]), begin(c[0]) + (id0 + 1), end(c[0]));
rotate(begin(c[1]), begin(c[1]) + id1, end(c[1]));
for (int i : c[1])
c[0].push_back(i);
return c[0];
}
Compilation message
longesttrip.cpp: In function 'std::vector<int> longest_trip(int, int)':
longesttrip.cpp:60:75: error: 'x' was not declared in this scope
60 | if (are_connected(vector<int>(begin(c[1]) + low, begin(c[1]) + mid), {x})) high = mid;
| ^
longesttrip.cpp:60:77: error: could not convert '{<expression error>}' from '<brace-enclosed initializer list>' to 'std::vector<int>'
60 | if (are_connected(vector<int>(begin(c[1]) + low, begin(c[1]) + mid), {x})) high = mid;
| ^
| |
| <brace-enclosed initializer list>
longesttrip.cpp:65:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
65 | if (id0 < size(c[0]) - 1)
| ~~~~^~~~~~~~~~~~~~~~
