实验6.3
task3.1
1 #include <iostream>
2 #include <fstream>
3 #include <array>
4 #define N 5
5
6 int main() {
7 using namespace std;
8
9 array<int, N> x {97, 98, 99, 100, 101};
10
11 ofstream out;
12 out.open("data1.dat", ios::binary);
13 if(!out.is_open()) {
14 cout << "fail to open data1.dat\n";
15 return 1;
16 }
17
18 out.write(reinterpret_cast<char *>(&x), sizeof(x));
19 out.close();
20 }
task3.2
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 }
用int整型存储每个数字占4个字节；存在文本文件中4个字节为一个单位，而给的数字仅需一个字节存储，剩下的三个字节为空，task2以字节形式读入，读入5个字节。
task4
Vector.hpp
1 #pragma once
2 #include<iostream>
3 using namespace std;
4 template<typename T>
5 class Vector {
6 public:
7 Vector(int n) ;
8 Vector(int n, T value);
9 Vector(const Vector<T>& v);
10 ~Vector(){delete []p;}
11 int get_size() { return size; }
12 T &at(int i);
13 T &operator[](int i);
14 template<typename T1>
15 friend void output(Vector<T1> &C);
16 private:
17 int size;
18 T* p;
19 };
20 template<typename T>
21 Vector<T>::Vector(int n){
22 size=n;
23 p = new T[size];
24 }
25 template<typename T>
26 Vector<T>::Vector(int n, T value) :size{n} {
27 p = new T[size];
28 for (int i = 0; i < size; i++)
29 p[i] = value;
30 }
31 template<typename T>
32 Vector<T>::Vector(const Vector<T>& C) : size{ C.size } {
33 p= new T[size];
34 for (int i = 0; i < size; i++)
35 p[i] = C.p[i];
36 }
37 template<typename T>
38 T &Vector<T>::at(int i){
39 return p[i];
40 }
41 template<typename T>
42 T &Vector<T>::operator[](int i){
43 return p[i];
44 }
45 template<typename T1>
46 void output( Vector<T1> &C) {
47 for (int i = 0; i < C.size; i++)
48 cout << C[i] << ", ";
49 cout << "\b\b \n";
50 }
task4.cpp
1 #include <iostream>
2 #include "Vector.hpp"
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 * 0.7;
13
14 output(x1);
15
16 Vector<int> x2(n, 6);
17 Vector<int> x3(x2);
18
19 output(x2);
20 output(x3);
21
22 x2.at(0) = 77;
23 output(x2);
24
25 x3[0] = 909;
26 output(x3);
27 }
28
29 int main() {
30 test();
31 }
task5.cpp
1 #include<iostream>
2 #include <fstream>
3 #include <iomanip>
4 using namespace std;
5 void output(std::ostream &out);
6 int main(){
7 ofstream fout;
8 fout.open("cipher_key.txt");
9 if(!fout.is_open()){
10 cout<<"fail to open file "<<"cipher_key"<<endl;
11 }
12 output(fout);
13 fout.close();
14 output(cout);
15
16 }
17 void output(std::ostream &out){
18 char code[26];
19 char Code[26];
20 for(int i=0;i<26;i++){
21 code[i]='a'+i;
22 }
23 out<<" ";
24 for(int i=0;i<26;i++){
25 out<<code[i]<<" ";
26 }
27 out<<"\n";
28 for(int i=1;i<=26;i++){
29 for(int t=0;t<26;t++){
30
31 if(t+i<=25){
32 Code[t]='A'+t+i;
33 }
34 else if(t+i>25){
35 Code[t]='A'+t+i-25-1;
36 }
37 }
38 out<<setw(2)<<i<<" ";
39 for(int t=0;t<26;t++){
40 out<<Code[t]<<" ";
41 }
42 out<<"\n";
43
44 }
45 }
标签：int,Vector,实验,template,output,include,size From： https://www.cnblogs.com/gzj035/p/16947219.html