#include "mushrooms.h"
#include <bits/stdc++.h>
using namespace std;
const int INF = 1e9;
int BLOCK;
int count_mushrooms(int n) {
int mn = INF;
for (int i = 1; i <= n; i++) {
int nw = 2*i + (n-(2*i)) / i;
if (nw < mn) {
mn = nw;
BLOCK = i;
}
}
//cout << BLOCK << '\n';
int fin;
vector<int> A = {0}, B, Q;
for (fin = 1; fin <= 2*BLOCK; fin++) {
int t = use_machine({0, fin});
if (t) {B.push_back(fin);}
else {A.push_back(fin);}
if (max(A.size(), B.size()) >= (int)(BLOCK+1)) {break;}
}
//for (auto &i : A) cout << i << ' '; cout << '\n';
//for (auto &i : B) cout << i << ' '; cout << '\n';
int ans = A.size();
bool useB = 0;
if (B.size() >= (int)(BLOCK+1)) {useB = 1;}
for (fin++; fin < n; fin++) {Q.push_back(fin);}
//for (auto &i : Q) cout << i << ' '; cout << '\n';
if (!useB) {
while (!Q.empty()) {
vector<int> ask = {A[0]};
int inMachine = 0;
for (int i = 1; (!Q.empty()) && (i < (int)A.size()); i++) {
ask.push_back(Q.back());
Q.pop_back();
ask.push_back(A[i]);
inMachine++;
}
int tmp = use_machine(ask);
ans += inMachine - (tmp/2);
}
} else {
while (!Q.empty()) {
vector<int> ask = {B[0]};
int inMachine = 0;
for (int i = 1; (!Q.empty()) && (i < (int)A.size()); i++) {
ask.push_back(Q.back());
Q.pop_back();
ask.push_back(B[i]);
inMachine++;
}
int tmp = use_machine(ask);
ans += tmp/2;
}
}
return ans;
}
#ifdef Zanite
static char fmt_buffer[100000];
#define FMT_TO_STR(fmt, result) va_list vargs; va_start(vargs, fmt); \
vsnprintf(fmt_buffer, sizeof(fmt_buffer), fmt, vargs); \
va_end(vargs); fmt_buffer[sizeof(fmt_buffer)-1] = 0; \
std::string result(fmt_buffer);
static const int min_n = 2;
static const int max_n = 20000;
static const int max_qc = 20000;
static const int max_qs = 100000;
static const int species_A = 0;
static const int species_B = 1;
static int n;
static std::vector<int> species;
static int qc, qs;
static inline void error_if(bool cond, std::string message) {
if (cond) {
printf("%s\n", message.c_str());
exit(0);
}
}
static inline void wrong_if(bool cond, std::string message) {
error_if(cond, "Wrong Answer: "+message);
}
int use_machine(std::vector<int> x) {
const int xs = x.size();
wrong_if(xs < 2, "Too small array for query.");
wrong_if(xs > n, "Too large array for query.");
qc++;
wrong_if(qc > max_qc, "Too many queries.");
qs += xs;
wrong_if(qs > max_qs, "Too many total array sizes as queries.");
for (int i = 0; i < xs; i++)
wrong_if(x[i] < 0 || n - 1 < x[i], "Invalid value in the query array.");
std::vector<bool> used(n, false);
for (int i = 0; i < xs; i++) {
wrong_if(used[x[i]], "Duplicate value in the query array.");
used[x[i]] = true;
}
int diffs = 0;
for (int i = 1; i < xs; i++)
diffs += int(species[x[i]] != species[x[i-1]]);
return diffs;
}
#ifdef __GNUC__
__attribute__ ((format(printf, 2, 3)))
#endif
static inline void check_input(bool cond, const char* message_fmt, ...) {
FMT_TO_STR(message_fmt, message);
error_if(!cond, "Invalid input: "+message);
}
int main() {
check_input(1 == scanf("%d", &n), "Could not read n.");
check_input(min_n <= n, "n must not be less than %d, but it is %d.", min_n, n);
check_input(n <= max_n, "n must not be greater than %d, but it is %d.", max_n, n);
species.resize(n);
for (int i = 0; i < n; i++) {
check_input(1 == scanf("%d", &species[i]), "Could not read species element [%d].", i);
check_input(species[i]==species_A || species[i] == species_B,
"Species elements must be %d or %d, but species element [%d] is %d.", species_A, species_B, i, species[i]);
}
check_input(species[0] == species_A, "Species element [%d] must be %d.", 0, species_A);
// Postponed closing standard input in order to allow interactive usage of the grader.
qc = 0;
qs = 0;
int answer = count_mushrooms(n);
printf("%d\n%d\n", answer, qc);
fclose(stdout);
fclose(stdin);
return 0;
}
#endif
