#include #include using namespace std; class Matrix { double data[9]; double getMinorAt(int i) const { double tmp[4]; int k = 0; for(int j = 0; j < 9; j++) if(i % 3 != j % 3 && i / 3 != j / 3) tmp[k++] = data[j]; if(i % 2 == 0) return tmp[0]*tmp[3] - tmp[1]*tmp[2]; else return tmp[1]*tmp[2] - tmp[0]*tmp[3]; } Matrix minors() const { Matrix res; for(int i = 0; i < 9; i++) res.data[i] = getMinorAt(i); return res; } Matrix T() const { Matrix res; for(int y = 0; y < 3; y++) for(int x = 0; x < 3; x++) res.data[x*3+y] = data[y*3+x]; return res; } public: Matrix() {} Matrix(const double* arr) { for(int i = 0; i < 9; i++) data[i] = arr[i]; } double* apply(const double* v) const { #define d data double* res = new double[3]; res[0] = d[0]*v[0] + d[1]*v[1] + d[2]*v[2]; res[1] = d[3]*v[0] + d[4]*v[1] + d[5]*v[2]; res[2] = d[6]*v[0] + d[7]*v[1] + d[8]*v[2]; return res; } double det() const { #define d data return d[0]*d[4]*d[8] - d[2]*d[4]*d[6] + d[1]*d[5]*d[6] - d[0]*d[5]*d[7] + d[2]*d[3]*d[7] - d[1]*d[3]*d[8]; } Matrix inverse() const { Matrix res = minors().T(); double det = this->det(); for(int i = 0; i < 9; i++) res.data[i] /= det; return res; } friend ostream& operator<<(ostream&, const Matrix&); }; ostream& operator<<(ostream& s, const Matrix& m) { s << "["; for(int i = 0; i < 9; i++) { s << setw(6) << setprecision(5) << m.data[i]; if(i != 8) s << " "; if((i+1) % 3 == 0 && i != 8) s << "\n "; } s << "]\n"; return s; } double* encrypt(const double* data, int size, const Matrix& key) { double* res = new double[(size+2)/3*3]; for(int i = 0; i < size; i += 3) { double tmp[3] = { data[i] }; if(i + 1 < size) tmp[1] = data[i+1]; else tmp[1] = 0; if(i + 2 < size) tmp[2] = data[i+2]; else tmp[2] = 0; double* enc = key.apply(tmp); for(int j = 0; j < 3; j++) res[i+j] = enc[j]; delete[] enc; } return res; } double* encryptStr(const string& s, const Matrix& key) { double* data = new double[s.length()]; for(int i = 0; i < s.length(); i++) data[i] = s[i]; double* res = encrypt(data, s.length(), key); delete[] data; return res; } void doubleValuesTest() { double keys[] = {2, 1, 0, 0, 2, 0, 0, 0, 2}; Matrix m(keys); Matrix inv = m.inverse(); cout << "Matrix:\n" << m; cout << "det: " << m.det() << endl; cout << "Inversed:\n" << inv << endl; double data1[] = {5, 7, 3, 1, 8, 2, 3}; cout << "input data: "; for(int i = 0; i < 7; i++) cout << data1[i] << " "; cout << endl; double* data2 = encrypt(data1, 7, m); cout << "transformed: "; for(int i = 0; i < 7; i++) cout << data2[i] << " "; cout << endl; double* data3 = encrypt(data2, 7, inv); cout << "inverse: "; for(int i = 0; i < 7; i++) cout << data3[i] << " "; cout << endl; delete[] data2, data3; } void strTest() { double keys[] = {3, 4, 1, 7, 6, 3, 8, 9, 1}; Matrix m(keys); Matrix inv = m.inverse(); string data1 = "hello"; cout << "input: " << data1 << endl; double* data2 = encryptStr(data1, m); cout << "encrypted: "; for(int i = 0; i < data1.length(); i++) cout << data2[i] << " "; cout << endl; delete[] data2; } int main() { strTest(); return 0; }

data encryption