4fd800b3a8 2011-02-23 kinaba: #include <iostream> 4fd800b3a8 2011-02-23 kinaba: #include <sstream> 4fd800b3a8 2011-02-23 kinaba: #include <iomanip> 4fd800b3a8 2011-02-23 kinaba: #include <vector> 4fd800b3a8 2011-02-23 kinaba: #include <string> 4fd800b3a8 2011-02-23 kinaba: #include <map> 4fd800b3a8 2011-02-23 kinaba: #include <set> 4fd800b3a8 2011-02-23 kinaba: #include <algorithm> 4fd800b3a8 2011-02-23 kinaba: #include <numeric> 4fd800b3a8 2011-02-23 kinaba: #include <iterator> 4fd800b3a8 2011-02-23 kinaba: #include <functional> 4fd800b3a8 2011-02-23 kinaba: #include <complex> 4fd800b3a8 2011-02-23 kinaba: #include <queue> 4fd800b3a8 2011-02-23 kinaba: #include <stack> 4fd800b3a8 2011-02-23 kinaba: #include <cmath> 4fd800b3a8 2011-02-23 kinaba: #include <cassert> 4fd800b3a8 2011-02-23 kinaba: #include <cstring> 4fd800b3a8 2011-02-23 kinaba: using namespace std; 4fd800b3a8 2011-02-23 kinaba: typedef long long LL; 4fd800b3a8 2011-02-23 kinaba: typedef complex<double> CMP; 4fd800b3a8 2011-02-23 kinaba: 4fd800b3a8 2011-02-23 kinaba: struct byLength { 4fd800b3a8 2011-02-23 kinaba: bool operator()(const string& lhs, const string& rhs) const { 4fd800b3a8 2011-02-23 kinaba: if(lhs.size() != rhs.size()) return lhs.size() < rhs.size(); 4fd800b3a8 2011-02-23 kinaba: return lhs < rhs; 4fd800b3a8 2011-02-23 kinaba: } 4fd800b3a8 2011-02-23 kinaba: }; 4fd800b3a8 2011-02-23 kinaba: class PrefixFreeSubsets { public: 4fd800b3a8 2011-02-23 kinaba: long long cantPrefFreeSubsets(vector <string> words) 4fd800b3a8 2011-02-23 kinaba: { 4fd800b3a8 2011-02-23 kinaba: int N = words.size(); 4fd800b3a8 2011-02-23 kinaba: sort(words.begin(), words.end(), byLength()); 4fd800b3a8 2011-02-23 kinaba: 4fd800b3a8 2011-02-23 kinaba: vector< vector<int> > dc; 4fd800b3a8 2011-02-23 kinaba: for(int i=0; i<N; ++i) 4fd800b3a8 2011-02-23 kinaba: dc.push_back( direct_children(words[i], words, i+1) ); 4fd800b3a8 2011-02-23 kinaba: dc.push_back( direct_children("", words, 0) ); 4fd800b3a8 2011-02-23 kinaba: return rec(N, dc) - 1; 4fd800b3a8 2011-02-23 kinaba: } 4fd800b3a8 2011-02-23 kinaba: 4fd800b3a8 2011-02-23 kinaba: LL rec(int t, vector< vector<int> >& dc ) 4fd800b3a8 2011-02-23 kinaba: { 4fd800b3a8 2011-02-23 kinaba: LL p = 1; 4fd800b3a8 2011-02-23 kinaba: for(int i=0; i<dc[t].size(); ++i) 4fd800b3a8 2011-02-23 kinaba: p *= rec(dc[t][i], dc); 4fd800b3a8 2011-02-23 kinaba: return p+1; 4fd800b3a8 2011-02-23 kinaba: } 4fd800b3a8 2011-02-23 kinaba: 4fd800b3a8 2011-02-23 kinaba: bool is_prefix(const string& pre, const string& all) { 4fd800b3a8 2011-02-23 kinaba: return equal(pre.begin(), pre.end(), all.begin()); 4fd800b3a8 2011-02-23 kinaba: } 4fd800b3a8 2011-02-23 kinaba: 4fd800b3a8 2011-02-23 kinaba: vector<int> direct_children(const string& s, vector<string>& w, int i) { 4fd800b3a8 2011-02-23 kinaba: vector<int> ans; 4fd800b3a8 2011-02-23 kinaba: for(; i<w.size(); ++i) 4fd800b3a8 2011-02-23 kinaba: if( is_prefix(s,w[i]) ){ 4fd800b3a8 2011-02-23 kinaba: bool direct = true; 4fd800b3a8 2011-02-23 kinaba: for(int j=0; j<ans.size(); ++j) 4fd800b3a8 2011-02-23 kinaba: direct = direct && !is_prefix(w[ans[j]], w[i]); 4fd800b3a8 2011-02-23 kinaba: if( direct ) 4fd800b3a8 2011-02-23 kinaba: ans.push_back(i); 4fd800b3a8 2011-02-23 kinaba: } 4fd800b3a8 2011-02-23 kinaba: return ans; 4fd800b3a8 2011-02-23 kinaba: } 4fd800b3a8 2011-02-23 kinaba: }; 4fd800b3a8 2011-02-23 kinaba: 4fd800b3a8 2011-02-23 kinaba: // BEGIN CUT HERE 4fd800b3a8 2011-02-23 kinaba: #include <ctime> 4fd800b3a8 2011-02-23 kinaba: double start_time; string timer() 4fd800b3a8 2011-02-23 kinaba: { ostringstream os; os << " (" << int((clock()-start_time)/CLOCKS_PER_SEC*1000) << " msec)"; return os.str(); } 4fd800b3a8 2011-02-23 kinaba: template<typename T> ostream& operator<<(ostream& os, const vector<T>& v) 4fd800b3a8 2011-02-23 kinaba: { os << "{ "; 4fd800b3a8 2011-02-23 kinaba: for(typename vector<T>::const_iterator it=v.begin(); it!=v.end(); ++it) 4fd800b3a8 2011-02-23 kinaba: os << '\"' << *it << '\"' << (it+1==v.end() ? "" : ", "); os << " }"; return os; } 4fd800b3a8 2011-02-23 kinaba: void verify_case(const long long& Expected, const long long& Received) { 4fd800b3a8 2011-02-23 kinaba: bool ok = (Expected == Received); 4fd800b3a8 2011-02-23 kinaba: if(ok) cerr << "PASSED" << timer() << endl; else { cerr << "FAILED" << timer() << endl; 4fd800b3a8 2011-02-23 kinaba: cerr << "\to: \"" << Expected << '\"' << endl << "\tx: \"" << Received << '\"' << endl; } } 4fd800b3a8 2011-02-23 kinaba: #define CASE(N) {cerr << "Test Case #" << N << "..." << flush; start_time=clock(); 4fd800b3a8 2011-02-23 kinaba: #define END verify_case(_, PrefixFreeSubsets().cantPrefFreeSubsets(words));} 4fd800b3a8 2011-02-23 kinaba: int main(){ 4fd800b3a8 2011-02-23 kinaba: 4fd800b3a8 2011-02-23 kinaba: CASE(0) 4fd800b3a8 2011-02-23 kinaba: string words_[] = {"hello","hell","hi"}; 4fd800b3a8 2011-02-23 kinaba: vector <string> words(words_, words_+sizeof(words_)/sizeof(*words_)); 4fd800b3a8 2011-02-23 kinaba: long long _ = 6LL; 4fd800b3a8 2011-02-23 kinaba: END 4fd800b3a8 2011-02-23 kinaba: CASE(1) 4fd800b3a8 2011-02-23 kinaba: string words_[] = {"a","b","c","d"}; 4fd800b3a8 2011-02-23 kinaba: vector <string> words(words_, words_+sizeof(words_)/sizeof(*words_)); 4fd800b3a8 2011-02-23 kinaba: long long _ = 16LL; 4fd800b3a8 2011-02-23 kinaba: END 4fd800b3a8 2011-02-23 kinaba: CASE(2) 4fd800b3a8 2011-02-23 kinaba: string words_[] = {"a","ab","abc","abcd","abcde","abcdef"}; 4fd800b3a8 2011-02-23 kinaba: vector <string> words(words_, words_+sizeof(words_)/sizeof(*words_)); 4fd800b3a8 2011-02-23 kinaba: long long _ = 7LL; 4fd800b3a8 2011-02-23 kinaba: END 4fd800b3a8 2011-02-23 kinaba: CASE(3) 4fd800b3a8 2011-02-23 kinaba: string words_[] = {"a","b","aa","ab","ba","bb"}; 4fd800b3a8 2011-02-23 kinaba: vector <string> words(words_, words_+sizeof(words_)/sizeof(*words_)); 4fd800b3a8 2011-02-23 kinaba: long long _ = 25LL; 4fd800b3a8 2011-02-23 kinaba: END 4fd800b3a8 2011-02-23 kinaba: 4fd800b3a8 2011-02-23 kinaba: } 4fd800b3a8 2011-02-23 kinaba: // END CUT HERE