Artifact 707c8d59bdc01e9a979419a1018c0f6428982779
#include <iostream>
#include <sstream>
#include <iomanip>
#include <vector>
#include <string>
#include <map>
#include <set>
#include <algorithm>
#include <numeric>
#include <iterator>
#include <functional>
#include <complex>
#include <queue>
#include <stack>
#include <cmath>
#include <cassert>
#include <cstring>
using namespace std;
typedef long long LL;
typedef complex<double> CMP;
class BunnyConverter { public:
vector< vector<int> > n_sqrt;
int getMinimum(int n, int z, int start, int goal)
{
n_sqrt.resize(n);
for(LL y=0; y<n; ++y)
n_sqrt[y*y%n].push_back(int(y?y:n));
set<int> v;
v.insert(start);
vector<int> q(1,start);
for(int step=0; !q.empty(); ++step)
{
vector<int> qNext;
for(int i=0; i<q.size(); ++i)
{
int x = q[i];
if( x == goal )
return step;
const vector<int>& ys = next(x,z,n);
for(int j=0; j<ys.size(); ++j)
{
int y = ys[j];
if( v.insert(y).second )
qNext.push_back(y);
}
}
q.swap(qNext);
}
return -1;
}
const vector<int>& next(LL x, LL z, LL n)
{
x %= n;
z %= n;
#define SUB(a,b) (((a)+n-(b))%n)
#define MUL(a,b) ((a)*(b)%n)
LL y2 = SUB(SUB(0, x), MUL(z,MUL(z,z)));
return n_sqrt[int(y2)];
}
};
// BEGIN CUT HERE
#include <ctime>
double start_time; string timer()
{ ostringstream os; os << " (" << int((clock()-start_time)/CLOCKS_PER_SEC*1000) << " msec)"; return os.str(); }
template<typename T> ostream& operator<<(ostream& os, const vector<T>& v)
{ os << "{ ";
for(typename vector<T>::const_iterator it=v.begin(); it!=v.end(); ++it)
os << '\"' << *it << '\"' << (it+1==v.end() ? "" : ", "); os << " }"; return os; }
void verify_case(const int& Expected, const int& Received) {
bool ok = (Expected == Received);
if(ok) cerr << "PASSED" << timer() << endl; else { cerr << "FAILED" << timer() << endl;
cerr << "\to: \"" << Expected << '\"' << endl << "\tx: \"" << Received << '\"' << endl; } }
#define CASE(N) {cerr << "Test Case #" << N << "..." << flush; start_time=clock();
#define END verify_case(_, BunnyConverter().getMinimum(n, z, start, goal));}
int main(){
CASE(0)
int n = 5;
int z = 1;
int start = 5;
int goal = 3;
int _ = 1;
END
CASE(1)
int n = 5;
int z = 1;
int start = 5;
int goal = 1;
int _ = 2;
END
CASE(2)
int n = 6;
int z = 2;
int start = 3;
int goal = 4;
int _ = -1;
END
CASE(3)
int n = 7;
int z = 7;
int start = 7;
int goal = 7;
int _ = 0;
END
CASE(4)
int n = 499979;
int z = 499979;
int start = 499976;
int goal = 3;
int _ = 249988;
END
/*
CASE(5)
int n = ;
int z = ;
int start = ;
int goal = ;
int _ = ;
END
CASE(6)
int n = ;
int z = ;
int start = ;
int goal = ;
int _ = ;
END
*/
}
// END CUT HERE