oop实验一
实验一:
task1:
源代码:
1 #include <iostream> 2 #include <string> 3 #include <vector> 4 #include <algorithm> 5 6 template<typename T> 7 void output(const T &c); 8 9 void test1(); 10 void test2(); 11 void test3(); 12 13 int main() { 14 std::cout << "测试1: \n"; 15 test1(); 16 17 std::cout << "\n测试2: \n"; 18 test2(); 19 20 std::cout << "\n测试3: \n"; 21 test3(); 22 } 23 24 template <typename T> 25 void output(const T &c) { 26 for(auto &i : c) 27 std::cout << i << ' '; 28 std::cout << '\n'; 29 } 30 31 void test1() { 32 using namespace std; 33 34 string s0{"0123456789"}; 35 cout << "s0 = " << s0 << endl; 36 37 string s1(s0); 38 reverse(s1.begin(), s1.end()); 39 cout << "s1 = " << s1 << endl; 40 41 string s2(s0.size(), ' '); 42 reverse_copy(s0.begin(), s0.end(), s2.begin()); 43 cout << "s2 = " << s2 << endl; 44 } 45 46 void test2() { 47 using namespace std; 48 49 vector<int> v0{2, 0, 4, 9}; 50 cout << "v0: "; output(v0); 51 52 vector<int> v1{v0}; 53 reverse(v1.begin(), v1.end()); 54 cout << "v1: "; output(v1); 55 56 vector<int> v2{v0}; 57 reverse_copy(v0.begin(), v0.end(), v2.begin()); 58 cout << "v2: "; output(v2); 59 } 60 61 void test3() { 62 using namespace std; 63 64 vector<int> v0{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; 65 cout << "v0: "; output(v0); 66 67 vector<int> v1{v0}; 68 rotate(v1.begin(), v1.begin()+1, v1.end()); 69 cout << "v1: "; output(v1); 70 71 vector<int> v2{v0}; 72 rotate(v2.begin(), v2.begin()+2, v2.end()); 73 cout << "v2: "; output(v2); 74 75 vector<int> v3{v0}; 76 rotate(v3.begin(), v3.end()-1, v3.end()); 77 cout << "v3: "; output(v3); 78 79 vector<int> v4{v0}; 80 rotate(v4.begin(), v4.end()-2, v4.end()); 81 cout << "v4: "; output(v4); 82 }
运行截图:
问题1:reverse修改操作的元素,并且无返回值;reverse_copy因为其后缀执行赋值操作,不修改元素,将反转后的元素复制到新的地址
问题2:rotate将前面容器的元素送到后面容器的最后面
其中first 代表容器的起始迭代器;middle代表从first到此为止的元素需要被移至后面;last代表容器结束的迭代器
task2:
源代码:
1 #include <iostream> 2 #include <vector> 3 #include <algorithm> 4 #include <numeric> 5 #include <iomanip> 6 #include <cstdlib> 7 #include <ctime> 8 9 template<typename T> 10 void output(const T &c); 11 12 int generate_random_number(); 13 void test1(); 14 void test2(); 15 16 int main() { 17 std::srand(std::time(0)); 18 std::cout << "测试1: \n"; 19 test1(); 20 21 std::cout << "\n测试2: \n"; 22 test2(); 23 } 24 25 template <typename T> 26 void output(const T &c) { 27 for(auto &i: c) 28 std::cout << i << ' '; 29 std::cout << '\n'; 30 } 31 32 int generate_random_number() { 33 return std::rand() % 101; 34 } 35 36 void test1() { 37 using namespace std; 38 39 vector<int> v0(10); 40 generate(v0.begin(), v0.end(), generate_random_number); 41 cout << "v0: "; output(v0); 42 43 vector<int> v1{v0}; 44 sort(v1.begin(), v1.end()); 45 cout << "v1: "; output(v1); 46 47 vector<int> v2{v0}; 48 sort(v2.begin()+1, v2.end()-1); 49 cout << "v2: "; output(v2); 50 } 51 52 void test2() { 53 using namespace std; 54 55 vector<int> v0(10); 56 generate(v0.begin(), v0.end(), generate_random_number); 57 cout << "v0: "; output(v0); 58 59 auto min_iter = min_element(v0.begin(), v0.end()); 60 auto max_iter = max_element(v0.begin(), v0.end()); 61 cout << "最小值: " << *min_iter << endl; 62 cout << "最大值: " << *max_iter << endl; 63 64 auto ans = minmax_element(v0.begin(), v0.end()); 65 cout << "最小值: " << *(ans.first) << endl; 66 cout << "最大值: " << *(ans.second) << endl; 67 68 double avg1 = accumulate(v0.begin(), v0.end(), 0.0) / v0.size(); 69 cout << "均值: " << fixed << setprecision(2) << avg1 << endl; 70 71 sort(v0.begin(), v0.end()); 72 double avg2 = accumulate(v0.begin()+1, v0.end()-1, 0.0) / (v0.size()-2); 73 cout << "去掉最大值、最小值之后,均值: " << avg2 << endl; 74 }
运行截图:
问题1:generate用来调用函数完成批量赋值的操作
问题2:效率比较高,时间复杂度更低,遍历的操作只需要一次
问题3:lambda更适合复杂度更低的场景,更加便利,逻辑性稍微差一些
task3:
源代码:
1 #include <iostream> 2 #include <string> 3 #include <algorithm> 4 #include <cctype> 5 6 unsigned char func(unsigned char c); 7 void test1(); 8 void test2(); 9 10 int main() { 11 std::cout << "测试1: 字符串大小写转换\n"; 12 test1(); 13 14 std::cout << "\n测试2: 字符变换\n"; 15 test2(); 16 } 17 18 unsigned char func(unsigned char c) { 19 if(c == 'z') 20 return 'a'; 21 22 if(c == 'Z') 23 return 'A'; 24 25 if(std::isalpha(c)) 26 return static_cast<unsigned char>(c+1); 27 28 return c; 29 } 30 31 void test1() { 32 std::string s1{"Hello World 2049!"}; 33 std::cout << "s1 = " << s1 << '\n'; 34 35 std::string s2; 36 for(auto c: s1) 37 s2 += std::tolower(c); 38 std::cout << "s2 = " << s2 << '\n'; 39 40 std::string s3; 41 for(auto c: s1) 42 s3 += std::toupper(c); 43 std::cout << "s3 = " << s3 << '\n'; 44 } 45 46 void test2() { 47 std::string s1{"I love cosmos!"}; 48 std::cout << "s1 = " << s1 << '\n'; 49 50 std::string s2(s1.size(), ' '); 51 std::transform(s1.begin(), s1.end(), 52 s2.begin(), 53 func); 54 std::cout << "s2 = " << s2 << '\n'; 55 }
运行截图:
问题1:将输入的字符进行变换,返回下一个字母;不是字母就返回元字符
问题2:tolower将大写的字母变成小写的字母;toupper相反,将小写的字母变成大写的字母
问题3:它有四个参数,分别为输入的开始迭代器,输入的结束迭代器,输出的开始迭代器和转换过程需要的函数
s2_begin会导致转存,不修改原来的字符串;s1_begin会直接修改原来的字符串、
task4:
源代码:
1 #include <iostream> 2 #include <string> 3 #include <algorithm> 4 5 bool is_palindrome(const std::string &s); 6 bool is_palindrome_ignore_case(const std::string&s); 7 8 int main(){ 9 using namespace std; 10 string s; 11 while (cin>>s){ 12 cout << boolalpha 13 << "区分大小写:" <<is_palindrome(s)<< "\n" 14 << "不区分大小写:"<< is_palindrome_ignore_case(s)<< "\n\n"; 15 } 16 } 17 18 bool is_palindrome(const std::string&s){ 19 std::string rev_s=s; 20 std::reverse(rev_s.begin(),rev_s.end()); 21 return s==rev_s; 22 } 23 24 bool is_palindrome_ignore_case(const std::string&s){ 25 std::string lower_s=s; 26 for (char &c:lower_s){ 27 c=std::tolower(static_cast<unsigned char>(c)); 28 } 29 std::string rev_lower_s=lower_s; 30 std::reverse(rev_lower_s.begin(),rev_lower_s.end()); 31 return lower_s==rev_lower_s; 32 }
运行截图:
问题:将原来的cin>>s改成getline(cin,s)让他读取一整行的字符内容
task5:
源代码:
1 #include <iostream> 2 #include <string> 3 #include <algorithm> 4 5 std::string dec2n(int x,int n=2); 6 7 int main(){ 8 int x; 9 while(std::cin>>x) { 10 std::cout << "十进制: " <<x<< '\n' 11 << "二进制: " <<dec2n(x)<< '\n' 12 << "八进制: " <<dec2n(x,8)<< '\n' 13 << "十二进制: " <<dec2n(x,12)<< '\n' 14 << "十六进制: " <<dec2n(x,16)<< '\n' 15 << "三十二进制: " <<dec2n(x,32)<< "\n\n"; 16 } 17 } 18 19 std::string dec2n(int x, int n){ 20 if (x==0){ 21 return "0"; 22 } 23 std::string result; 24 const std::string digits = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"; 25 while(x>0){ 26 result+=digits[x%n]; 27 x=x/n; 28 } 29 std::reverse(result.begin(),result.end()); 30 return result; 31 }
运行截图:
task6:
源代码:
1 #include <iostream> 2 #include <string> 3 4 int main() { 5 std::cout<<" "; 6 for (char c = 'a'; c <= 'z'; ++c) { 7 std::cout << c << " "; 8 } 9 std::cout << std::endl; 10 11 std::string plain = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; 12 for (int i = 1; i <= 26; ++i) { 13 if (i < 10) { 14 std::cout<<" "; 15 std::cout << i << " "; 16 } else { 17 std::cout << i << " "; 18 } 19 for (int j = 0; j < 26; ++j) { 20 int pos = (j + i) % 26; 21 std::cout << plain[pos] << " "; 22 } 23 std::cout << std::endl; 24 } 25 26 return 0; 27 }
运行截图:
task7:
源代码:
1 #include <iostream> 2 #include <cstdlib> 3 #include <ctime> 4 #include <iomanip> 5 6 using namespace std; 7 8 int main(){ 9 srand(time(0)); 10 int correct=0; 11 for (int i=0;i<10;++i){ 12 int a=rand()%10+1; 13 int b=rand()%10+1; 14 int op=rand()%4; 15 int result,user_ans; 16 17 if(op==1){ 18 if(a<b)swap(a,b); 19 } 20 else if(op==3){ 21 while(a%b!=0){ 22 b=rand()%10+1; 23 } 24 } 25 26 switch(op){ 27 case 0:result=a+b;cout<<a<< " + " <<b<<" = ";break; 28 case 1:result=a-b;cout<<a<< " - " <<b<<" = ";break; 29 case 2:result=a*b;cout<<a<< " * " <<b<<" = ";break; 30 case 3:result=a/b;cout<<a<< " / " <<b<<" = ";break; 31 } 32 33 cin>>user_ans; 34 if(user_ans==result){ 35 correct++; 36 } 37 } 38 39 double accuracy=(double)correct/10*100; 40 cout<<"正确率:"<<fixed<<setprecision(2)<<accuracy<<"%"<<endl; 41 42 return 0; 43 }
运行截图:
实验一总结:
task5中对于进制转换式偷了懒,直接创建了序列去存储所有可能的进制转化是可能用到的字符,直接在字符处理时挑取并且组成结果,很爽。
task6中打印字母表同样使用这样的方法,创建序列后直接打印,需要用到的空格,以及数字靠右对齐都是用直接打印空格占据行数去实现,也很好用。
task7回忆了switch的用法去打印算术符号,在使用时遇到很多麻烦,比如输出不对应的问题,豆包给出的结果不如人意,kimi的方法又过于繁琐。
同时三个实验也用到了没有接触过的头函数,都是在ai 的辅助下使用。