Artifact e3b7dabae0461c08b2390791bb87d55f99b7ad43
#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>
#ifdef __GNUC__
#include <ext/hash_map>
#define unordered_map __gnu_cxx::hash_map
#else
#include <unordered_map>
#endif
using namespace std;
typedef long long LL;
typedef complex<double> CMP;
template<typename T>
struct DP2x
{
const int N1, N2;
vector<T> data;
DP2x(int, int N2, const T& t = T())
: N1(2), N2(N2), data(N1*N2, t) { assert(data.size()*sizeof(T)<(1<<26)); }
T& operator()(int i1, int i2)
{ i1&=1; return data[ (i1*N2)+i2 ]; }
void swap(DP2x& rhs)
{ data.swap(rhs.data); }
};
class SPartition { public:
long long getCount(string s)
{
if( s.size()%2 != 0 )
return 0;
int N = s.size()/2;
DP2x<LL> dp(s.size()+1, 1<<N);
for(int i=s.size(); i>=0; --i)
for(int bits=0,ni=min(N,i); bits<(1<<ni); ++bits)
{
if( i == s.size() )
dp(i,bits) = (bits==0 ? 1 : 0);
else {
if( bits == 0 ) {
dp(i, bits) = dp(i+1, 1) * 2;
} else {
int iMax = 0;
while( (2<<iMax) <= bits )
++iMax;
int oldb = s[i-1-iMax];
int newb = s[i];
LL tot = 0;
if( oldb == newb )
tot += dp(i+1, (bits &~ (1<<iMax))<<1);
if( (bits<<1 | 1) < (1<<N) )
tot += dp(i+1, bits<<1 | 1);
dp(i,bits) = tot;
}
}
}
return dp(0, 0);
}
};
// 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 long long& Expected, const long long& 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(_, SPartition().getCount(s));}
int main(){
CASE(0)
string s = "oxox";
long long _ = 2LL;
END
CASE(1)
string s = "oooxxx";
long long _ = 0LL;
END
CASE(2)
string s = "xoxxox";
long long _ = 4LL;
END
CASE(3)
string s = "xo";
long long _ = 0LL;
END
CASE(4)
string s = "ooooxoox";
long long _ = 8LL;
END
CASE(5)
string s = "ooxxoxox";
long long _ = 8LL;
END
CASE(6)
string s = "oxoxoxoxoxoxoxoxoxoxoxoxoxoxoxoxoxoxoxox";
long long _ = -1LL;
END
/*
CASE(7)
string s = ;
long long _ = LL;
END
*/
}
// END CUT HERE