实验六

实验任务3

#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;
    }

    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;
    }

    in.read(reinterpret_cast<char *>(&x), sizeof(x));
    in.close();

    for(auto i = 0; i < N; ++i)
        cout << x[i] << ", ";
    cout << "\b\b \n";
}

实验任务4

#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();
}

#pragma once
#include<cassert>
using namespace std;
template<typename T>
class Vector
{
    private:
        T l;
        T *p;
    public:
    Vector(int n) 
    {
        p=new T[n];
        l = n;
    }        
    ~Vector()
    {
        delete p;
    }
    Vector(const Vector<T> &a):l{a.l}
    {
    p=new T[l];
    for(int i=0;i<l;i++)
    {
        p[i]=a.p[i];
    }
    } 
    Vector(int n,T m):l{n}
    {
    p=new T[l];
    for(int i=0;i<l;i++)
    {
        p[i]=m;
    }
    }
    T &at(int index)
    {
        assert(index>=0&&index<l);
        return p[index];
    }
    int get_size()
    {
        return l;
    }
    T& operator[](int i)
    {
        return p[i];
    }
    friend void output(Vector &v)
    {
        int i;
        for(i=0;i<v.l-1;i++)
        {
            cout << v.p[i] << ",";
        }
        cout << v.p[i] << endl;
    }
};

实验任务5

#include<iostream>
#include<iomanip>
#include<string>
#include<fstream>
using namespace std;
void output(std::ostream &out)
{
    char a[26][26];
    cout<<"  ";
    out<<"  ";
    for(char i='a';i<='z';i++)
    {
        cout<<setw(2)<<setfill(' ')<<i;
        out<<setw(2)<<setfill(' ')<<i;
    }
    cout<<endl;
    out<<endl;
    for(int j=0;j<26;j++)
    {
        cout<<setw(2)<<setfill(' ')<<j+1;
        out<<setw(2)<<setfill(' ')<<j+1;
        for(int k=0;k<26;k++)
        {
            a[j][k]='A'+char((j+k+1)%26);
            cout<<setw(2)<<setfill(' ')<<a[j][k];
            out<<setw(2)<<setfill(' ')<<a[j][k];
        }
        out<<endl;
        cout<<endl;
    }
}
int main()
{
    ofstream out;
    out.open("cipher_key.txt",ios::out);
    if(!out.is_open())
    {
        cout<<"fail to open cipher_ke.text"<<endl;
        return 0;
    }
    output(out);
    out.close();
}