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: class AlternatingLane { public: 4fd800b3a8 2011-02-23 kinaba: double expectedBeauty(vector <int> low, vector <int> high) 4fd800b3a8 2011-02-23 kinaba: { 4fd800b3a8 2011-02-23 kinaba: double eSum = 0.0; 4fd800b3a8 2011-02-23 kinaba: for(int i=1; i<low.size(); ++i) 4fd800b3a8 2011-02-23 kinaba: { 4fd800b3a8 2011-02-23 kinaba: // ランダムに 4fd800b3a8 2011-02-23 kinaba: // h ∈ [low[i-1], high[i-1]] 4fd800b3a8 2011-02-23 kinaba: // g ∈ [low[i], high[i] ] 4fd800b3a8 2011-02-23 kinaba: // を取ってきたときの、|h-g| の期待値… 4fd800b3a8 2011-02-23 kinaba: double e = 0; 4fd800b3a8 2011-02-23 kinaba: for(int h=low[i-1]; h<=high[i-1]; ++h) 4fd800b3a8 2011-02-23 kinaba: if( h <= low[i] ) 4fd800b3a8 2011-02-23 kinaba: e += sequenceSum(low[i]-h, high[i]-h); 4fd800b3a8 2011-02-23 kinaba: else if( high[i] <= h ) 4fd800b3a8 2011-02-23 kinaba: e += sequenceSum(h-high[i], h-low[i]); 4fd800b3a8 2011-02-23 kinaba: else 4fd800b3a8 2011-02-23 kinaba: e += sequenceSum(0, h-low[i]) + sequenceSum(0, high[i]-h); 4fd800b3a8 2011-02-23 kinaba: eSum += e / (high[i]-low[i]+1) / (high[i-1]-low[i-1]+1); 4fd800b3a8 2011-02-23 kinaba: } 4fd800b3a8 2011-02-23 kinaba: return eSum; // …の和、が答え 4fd800b3a8 2011-02-23 kinaba: } 4fd800b3a8 2011-02-23 kinaba: 4fd800b3a8 2011-02-23 kinaba: LL sequenceSum(LL a, LL b) // a+(a+1)+...+b 4fd800b3a8 2011-02-23 kinaba: { 4fd800b3a8 2011-02-23 kinaba: return (a+b) * (b-a+1) / 2; 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 double& Expected, const double& Received) { 4fd800b3a8 2011-02-23 kinaba: bool ok = (abs(Expected - Received) < 1e-9); 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(_, AlternatingLane().expectedBeauty(low, high));} 4fd800b3a8 2011-02-23 kinaba: int main(){ 4fd800b3a8 2011-02-23 kinaba: 4fd800b3a8 2011-02-23 kinaba: CASE(0) 4fd800b3a8 2011-02-23 kinaba: int low_[] = {1}; 4fd800b3a8 2011-02-23 kinaba: vector <int> low(low_, low_+sizeof(low_)/sizeof(*low_)); 4fd800b3a8 2011-02-23 kinaba: int high_[] = {100}; 4fd800b3a8 2011-02-23 kinaba: vector <int> high(high_, high_+sizeof(high_)/sizeof(*high_)); 4fd800b3a8 2011-02-23 kinaba: double _ = 0.0; 4fd800b3a8 2011-02-23 kinaba: END 4fd800b3a8 2011-02-23 kinaba: CASE(1) 4fd800b3a8 2011-02-23 kinaba: int low_[] = {1, 1, 1}; 4fd800b3a8 2011-02-23 kinaba: vector <int> low(low_, low_+sizeof(low_)/sizeof(*low_)); 4fd800b3a8 2011-02-23 kinaba: int high_[] = {2, 2, 2}; 4fd800b3a8 2011-02-23 kinaba: vector <int> high(high_, high_+sizeof(high_)/sizeof(*high_)); 4fd800b3a8 2011-02-23 kinaba: double _ = 1.0; 4fd800b3a8 2011-02-23 kinaba: END 4fd800b3a8 2011-02-23 kinaba: CASE(2) 4fd800b3a8 2011-02-23 kinaba: int low_[] = {1, 3, 5, 7, 9}; 4fd800b3a8 2011-02-23 kinaba: vector <int> low(low_, low_+sizeof(low_)/sizeof(*low_)); 4fd800b3a8 2011-02-23 kinaba: int high_[] = {2, 4, 6, 8, 10}; 4fd800b3a8 2011-02-23 kinaba: vector <int> high(high_, high_+sizeof(high_)/sizeof(*high_)); 4fd800b3a8 2011-02-23 kinaba: double _ = 8.0; 4fd800b3a8 2011-02-23 kinaba: END 4fd800b3a8 2011-02-23 kinaba: CASE(3) 4fd800b3a8 2011-02-23 kinaba: int low_[] = {4, 3, 3, 7}; 4fd800b3a8 2011-02-23 kinaba: vector <int> low(low_, low_+sizeof(low_)/sizeof(*low_)); 4fd800b3a8 2011-02-23 kinaba: int high_[] = {10, 7, 7, 7}; 4fd800b3a8 2011-02-23 kinaba: vector <int> high(high_, high_+sizeof(high_)/sizeof(*high_)); 4fd800b3a8 2011-02-23 kinaba: double _ = 6.171428571428572; 4fd800b3a8 2011-02-23 kinaba: END 4fd800b3a8 2011-02-23 kinaba: CASE(4) 4fd800b3a8 2011-02-23 kinaba: int low_[] = {1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1}; 4fd800b3a8 2011-02-23 kinaba: vector <int> low(low_, low_+sizeof(low_)/sizeof(*low_)); 4fd800b3a8 2011-02-23 kinaba: int high_[] = {100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000,100000}; 4fd800b3a8 2011-02-23 kinaba: vector <int> high(high_, high_+sizeof(high_)/sizeof(*high_)); 4fd800b3a8 2011-02-23 kinaba: double _ = -1; 4fd800b3a8 2011-02-23 kinaba: END 4fd800b3a8 2011-02-23 kinaba: /* 4fd800b3a8 2011-02-23 kinaba: CASE(5) 4fd800b3a8 2011-02-23 kinaba: int low_[] = ; 4fd800b3a8 2011-02-23 kinaba: vector <int> low(low_, low_+sizeof(low_)/sizeof(*low_)); 4fd800b3a8 2011-02-23 kinaba: int high_[] = ; 4fd800b3a8 2011-02-23 kinaba: vector <int> high(high_, high_+sizeof(high_)/sizeof(*high_)); 4fd800b3a8 2011-02-23 kinaba: double _ = ; 4fd800b3a8 2011-02-23 kinaba: END 4fd800b3a8 2011-02-23 kinaba: */ 4fd800b3a8 2011-02-23 kinaba: } 4fd800b3a8 2011-02-23 kinaba: // END CUT HERE