結果
| 問題 | No.460 裏表ちわーわ |
| ユーザー |
 koyumeishi
|
| 提出日時 | 2016-12-11 06:04:57 |
| 言語 | C++14 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
AC
|
| 実行時間 | 12 ms / 2,000 ms |
| コード長 | 6,659 bytes |
| コンパイル時間 | 1,642 ms |
| コンパイル使用メモリ | 127,096 KB |
| 実行使用メモリ | 5,248 KB |
| 最終ジャッジ日時 | 2024-11-29 03:04:20 |
| 合計ジャッジ時間 | 2,476 ms |
|
ジャッジサーバーID （参考情報） |
judge1 / judge3 |
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| ファイルパターン | 結果 |
|---|---|
| other | AC * 28 |
ソースコード
#include <iostream>#include <vector>#include <cstdio>#include <sstream>#include <map>#include <string>#include <algorithm>#include <queue>#include <cmath>#include <functional>#include <set>#include <ctime>#include <random>#include <chrono>#include <cassert>#include <tuple>#include <utility>using namespace std;namespace {using Integer = long long; //__int128;template<class T, class S> istream& operator >> (istream& is, pair<T,S>& p){return is >> p.first >> p.second;}template<class T> istream& operator >> (istream& is, vector<T>& vec){for(T& val: vec) is >> val; return is;}template<class T> istream& operator , (istream& is, T& val){ return is >> val;}template<class T, class S> ostream& operator << (ostream& os, const pair<T,S>& p){return os << p.first << " " << p.second;}template<class T> ostream& operator << (ostream& os, const vector<T>& vec){for(size_t i=0; i<vec.size(); i++) os << vec[i] << (i==vec.size()-1?"":""); return os;}template<class T> ostream& operator , (ostream& os, const T& val){ return os << " " << val;}template<class H> void print(const H& head){ cout << head; }template<class H, class ... T> void print(const H& head, const T& ... tail){ cout << head << " "; print(tail...); }template<class ... T> void println(const T& ... values){ print(values...); cout << endl; }template<class H> void eprint(const H& head){ cerr << head; }template<class H, class ... T> void eprint(const H& head, const T& ... tail){ cerr << head << " "; eprint(tail...); }template<class ... T> void eprintln(const T& ... values){ eprint(values...); cerr << endl; }class range{ Integer start_, end_, step_; public: struct range_iterator{ Integer val, step_; range_iterator(Integer v, Integer step) : val(v),step_(step) {} Integer operator * (){return val;} void operator ++ (){val += step_;} bool operator != (range_iterator& x){return step_ > 0 ?val < x.val : val > x.val;} }; range(Integer len) : start_(0), end_(len), step_(1) {} range(Integer start, Integer end) : start_(start), end_(end), step_(1) {} range(Integer start, Integer end, Integer step) : start_(start), end_(end), step_(step) {} range_iterator begin(){ returnrange_iterator(start_, step_); } range_iterator end(){ return range_iterator( end_, step_); } };inline string operator "" _s (const char* str, size_t size){ return move(string(str)); }constexpr Integer my_pow(Integer x, Integer k, Integer z=1){return k==0 ? z : k==1 ? z*x : (k&1) ? my_pow(x*x,k>>1,z*x) : my_pow(x*x,k>>1,z);}constexpr Integer my_pow_mod(Integer x, Integer k, Integer M, Integer z=1){return k==0 ? z%M : k==1 ? z*x%M : (k&1) ? my_pow_mod(x*x%M,k>>1,M,z*x%M) : my_pow_mod(x*x%M,k>>1,M,z);}constexpr unsigned long long operator "" _ten (unsigned long long value){ return my_pow(10,value); }inline int k_bit(Integer x, int k){return (x>>k)&1;} //0-indexedmt19937 mt(chrono::duration_cast<chrono::nanoseconds>(chrono::steady_clock::now().time_since_epoch()).count());template<class T> string join(const vector<T>& v, const string& sep){ stringstream ss; for(size_t i=0; i<v.size(); i++){ if(i>0) ss << sep; ss <<v[i]; } return ss.str(); }inline string operator * (string s, int k){ string ret; while(k){ if(k&1) ret += s; s += s; k >>= 1; } return ret; }}constexpr long long mod = 9_ten + 7;int rank_;vector<int> xx;// A[n*p] * X[p*m] = B[n*m]template<class T = long long>vector<T> gaussian_elimination_binary(vector<T> A, vector<T> B, int n, int p, int m){vector<T> M(n);for(int i=0; i<n; i++){M[i] = A[i] << m;M[i] |= B[i];}int rank = 0;vector<int> left_most(n,-1);for(int row = 0, col = p+m-1; row<n && col>=m; col--){if( ((M[row] >> col) & T(1)) == T(0)){int pivot = row;for(int row__ = row; row__<n; row__++){if( ((M[row__] >> col) & T(1)) != T(0) ){pivot = row__;break;}}if(pivot == row) continue;swap(M[row], M[pivot]);}rank++;left_most[row] = col;for(int row__=row+1; row__<n; row__++){if( ((M[row__] >> col) & T(1)) != T(0) ) M[row__] ^= M[row];}row++;}rank_ = rank;xx = left_most;// T = long long//T mask_B = ((T)1<<m) - 1;//T mask_A = (((T)1<<(m+p)) - 1) ^ mask_B;// T = bitsetT mask_B( string(m, '1') );T mask_A( string(m+p, '1') );mask_A ^= mask_B;bool has_solution = true;for(int row=n-1; row>=0; row--){if( (M[row] & mask_B) != T(0) && (M[row] & mask_A) == T(0) ) has_solution = false;if(left_most[row] == -1) continue;int col = left_most[row];for(int row__ = row-1; row__>=0; row__--){if( ((M[row__] >> col) & T(1)) != T(0) ) M[row__] ^= M[row];}}return has_solution? M : vector<T>(0);}int dx[] = {0, 0, 1,-1, 1, 1,-1,-1};int dy[] = {1,-1, 0, 0, 1,-1, 1,-1};#include <bitset>using bits = bitset<65>;int main(){int n,m;cin >> n,m;vector<vector<int>> v(n, vector<int>(m));cin >> v;vector<bits> B(n*m);for(int i=0; i<n; i++){for(int j=0; j<m; j++){if( v[i][j] ) B[i*m+j].set(0);}}//eprintln("B\n", join(B,"\n"));vector<bits> A(n*m);for(int i=0; i<n; i++){for(int j=0; j<m; j++){A[i*m + j].set(i*m+j);for(int k=0; k<8; k++){int y = i+dy[k];int x = j+dx[k];if(y<0 || y>=n || x<0 || x>=m) continue;A[i*m+j].set(y*m+x);}}}//eprintln("A\n", join(A,"\n"));auto res = gaussian_elimination_binary(A,B, n*m, n*m, 1);for(auto& w:xx) w--;//eprintln(xx);if(res.size()==0){println("Impossible");return 0;}//eprintln( "res\n", join(res, "\n"));set<int> x; //freefor(int i=0; i<n*m; i++){x.insert(i);}for(int i : xx){x.erase(i);}int ans = 0;for(int i=0; i<m*n; i++){ans += res[i][0];}vector<vector<int>> C;for(int i : range(n*m)){if(xx[i] < 0) break;vector<int> tmp;for(int j=n*m; j>0; j--){if( res[i][j] ) tmp.push_back(j-1);}C.push_back(tmp);}for(int i=0; i<(1<<x.size()); i++){vector<int> tmp_x(n*m, -1);int k=0;for(auto w : x){if((i>>k) & 1) tmp_x[w] = 1;else tmp_x[w] = 0;k++;}int cnt = __builtin_popcount(i);for(int j=0; j<n*m && cnt < ans; j++){if(xx[j] < 0) break;int val = res[j][0];for(int l=1; l<C[j].size(); l++){val ^= tmp_x[ C[j][l] ];}if(val){tmp_x[ C[j][0] ] = 1;cnt++;}else{tmp_x[C[j][0]] = 0;}}ans = min(ans, cnt);}println(ans);return 0;}