实验六

task3

#include <iostream>
#include <fstream>
#include <array>
#define N 5
int main() {
    using namespace std;
    array<int, N> x{ 97, 98, 99, 100, 101 };
    ofstream out;
    out.open("data1.dat", ios::binary);
    if (!out.is_open()) {
        cout << "fail to open data1.dat\n";
        return 1;
    }
     //把从地址&x开始连续sizeof(x)个字节的数据块以字节数据块方式写入文件data1.txt
    out.write(reinterpret_cast<char*>(&x), sizeof(x));
    out.close();
}

#include <iostream>
#include <fstream>
#include <array>
#define N 5
int main() {
    using namespace std;
        array<int, N> x;
    ifstream in;
    in.open("data1.dat", ios::binary);
    if (!in.is_open()) {
        cout << "fail to open data1.dat\n";
        return 1;
    }
    // 从文件流对象in关联的文件data1.dat中读取sizeof(x)字节数据写入&x开始的地址单元
    in.read(reinterpret_cast<char*>(&x), sizeof(x));
    in.close();
    for (auto i = 0; i < N; ++i)
        cout << x[i] << ", ";
    cout << "\b\b \n";
}

 

 

 

 

task4

Vector.hpp

#pragma once
#include<iostream>
using namespace std;
template<typename T>
class Vector {
public:
    Vector() {};
    Vector(int n) :size{ n } {
        p = new T[size];
    }
    Vector(int n, T value) :size{ n } {
        p = new T[size];
        for (auto i = 0; i < n; i++) {
            p[i] = value;
        }
    }
    Vector(const Vector<T>& v1) : size{ v1.size }
    {
        p = new T[size];
        int i;
        for (i = 0; i < size; i++)
            p[i] = v1.p[i];
    }
    ~Vector() {
        delete[] p;
    }
    T& at(int index)
    {
        if (index >= 0 && index < size)
            return p[index];
    }

    friend void output(Vector<T>& v)
    {
        int i;
        for (i = 0; i < v.size; i++)
            cout << v[i] << " ";
        cout << endl;
    }

    int get_size()const
    {
        return size;
    }
    T& operator [](int index)
    {
        if (index >= 0 && index < size)
            return p[index];
    }
private:
    int size;
    T* p;

};

.cpp

#include <iostream>
#include "Vector.hpp"
void test() {
    using namespace std;
    int n;
    cin >> n;
    Vector<double> x1(n);
    for (auto i = 0; i < n; ++i)
        x1.at(i) = i * 0.7;
    output(x1);
    Vector<int> x2(n, 42);
    Vector<int> x3(x2);
    output(x2);
    output(x3);
    x2.at(0) = 77;
    output(x2);


    x3[0] = 999;
    output(x3);
}
int main() {
    test();
}

 

 

 task5

 

#include<bits/stdc++.h>
#include<iomanip>
using namespace std;

void output(ofstream &out){
    out.open("cipher_key.txt",ios::app);
    if(!out.is_open()){
        cout<<"fail to open cipher_key.txt"<<endl;
    }
    for(int i=0;i<=26;i++){
        if(i==0){
            cout<<"   ";
            out<<setw(2)<<left<<"   ";
        }else{
            cout<<setw(3)<<left<<i;
            out<<setw(3)<<left<<i;
        }
        for(int j=65;j<=90;j++){
            if(i==0){
                char x=j+32;
                cout<<setw(2)<<left<<x;
                out<<setw(2)<<left<<x;  
            }else{
                char x=(i+j-65)%26+65;
                cout<<setw(2)<<left<<x;
                out<<setw(2)<<left<<x;
            }
        }
        cout<<endl;
        out<<endl;
    }
    out.close();
}

int main(){
    ofstream out;
    output(out);    
    return 0;
}