实验六
1 #include <iostream> 2 #include <fstream> 3 #include <array> 4 #define N 5 5 6 int main() { 7 using namespace std; 8 array<char, N> x; 9 10 ifstream in; 11 in.open("data1.dat", ios::binary); 12 if (!in.is_open()) { 13 cout << "fail to open data1.dat\n"; 14 return 1; 15 } 16 17 in.read(reinterpret_cast<char*>(&x), sizeof(x)); 18 in.close(); 19 20 for (auto i = 0; i < N; ++i) 21 cout << x[i] << ", "; 22 cout << "\b\b \n"; 23 }
int占4个字节，char占1个字节
1 #pragma once 2 #include<iostream> 3 using namespace std; 4 template<typename T> 5 class Vector 6 { 7 public: 8 Vector(T n):size(n) 9 { 10 p = new T[n]; 11 } 12 Vector(T n, T value):size(n) 13 { 14 p = new T[n]; 15 for (int i = 0; i < size; i++) 16 { 17 p[i] = value; 18 } 19 } 20 Vector(const Vector<T>& r):size(r.size) 21 { 22 p = new int[size]; 23 for (int i = 0; i < size; i++) 24 p[i] = r.p[i]; 25 } 26 ~Vector() 27 { 28 delete[] p; 29 } 30 T& at(int i) 31 { 32 return p[i]; 33 } 34 T get_size() 35 { 36 return size; 37 } 38 friend void output(Vector<T>& x) 39 { 40 for (int i = 0; i < x.size; i++) 41 cout << x.p[i] << " "; 42 cout << endl; 43 } 44 T& operator[](int i) 45 { 46 return p[i]; 47 } 48 private: 49 T size; 50 T* p; 51 };
1 #include <iostream> 2 #include "Vector.h" 3 4 void test() { 5 using namespace std; 6 7 int n; 8 cin >> n; 9 10 Vector<double> x1(n); 11 for (auto i = 0; i < n; ++i) 12 x1.at(i) = i * 0.5; 13 14 output(x1); 15 16 Vector<int> x2(n, 66); 17 Vector<int> x3(x2); 18 19 output(x2); 20 output(x3); 21 22 x2.at(0) = 88; 23 output(x2); 24 25 x3[0] = 99; 26 output(x3); 27 } 28 29 int main() { 30 test(); 31 }
1 #include<iostream> 2 #include<iomanip> 3 #include<fstream> 4 using namespace std; 5 void output(std::ostream& out) 6 { 7 8 for (int i = 0; i < 27; i++) 9 { 10 if (!i) 11 { 12 out << " "; 13 for (int j = 97; j < 123; j++) 14 { 15 out << char(j) << " "; 16 } 17 out << endl; 18 continue; 19 } 20 out << std::left << setw(2) << i << " "; 21 for (int j = i; j < i + 26; j++) 22 { 23 out << std::left << setw(2) << char(65 + j % 26); 24 } 25 out << endl; 26 } 27 } 28 int main() 29 { 30 output(cout); 31 ofstream out; 32 out.open("cipher_key.txt"); 33 if (!out.is_open()) { 34 cout << "fail to open file cipher_key.txt to write" << endl; 35 return 0; 36 } 37 output(out); 38 out.close(); 39 }
