实验1 现代C++基础编程
task 1 实验代码：
#include<iostream> #include<string> #include<vector> #include<algorithm> using namespace std; //声明 //模板函数声明 template <typename T> void output(const T &c); //普通函数声明 void test1(); void test2(); void test3(); int main(){ cout<< "测试1：\n"; test1(); cout<<"\n测试2:\n"; test2(); cout<<"\n测试3:\n"; test3(); } //函数实现 //输出容器对象c中的元素 template <typename T> void output(const T &c){ for(auto &i:c) cout<<i<<" "; cout <<endl; } //测试1 //组合使用算法库，迭代器，string反转字符串 void test1(){ string s0{"0123456789"}; cout<< "s0 ="<<s0<<endl; string s1{s0}; reverse(s1.begin(),s1.end()); cout<< "s1 = "<<s1 <<endl; string s2{s0}; reverse_copy(s0.begin(),s0.end(),s2.begin()); cout<< "s2 = "<<s2<<endl; //测试2 //组合使用算法库迭代器，vector反转动态数组对象vector内数据 } void test2(){ vector<int> v0{2,0,4,9}; cout<<"v0: "; output(v0); vector<int> v1{v0}; reverse(v1.begin(),v1.end()); cout<< "v1: "; output(v1); vector<int> v2{v0}; reverse_copy(v0.begin(),v0.end(),v2.begin()); cout<<"v2: "; output(v2); } //测试3 //组合使用算法库迭代器，vector实现元素旋转移位 void test3() { vector<int> v0{0,1,2,3,4,5,6,7,8,9}; cout<<"v0: "; output(v0); vector<int> v1{v0}; rotate(v1.begin(),v1.begin()+1,v1.end()); cout<< "v1: "; output(v1); vector<int> v2{v0}; rotate(v2.begin(), v2.begin()+2, v2.end()); cout << "v2: "; output(v2); vector<int> v3{v0}; rotate(v3.begin(),v3.end()-1,v3.end()); cout<< "v3: "; output(v3); vector<int> v4{v0}; rotate(v4.begin(),v4.end()-2,v4.end()); cout<< "v4: "; output(v4); }
实验结果：
task 2 实验代码：
#include <iostream> #include <vector> #include <string> #include <algorithm> #include <numeric> #include <iomanip> using namespace std; // 函数声明 // 模板函数声明 template<typename T> void output(const T &c); // 普通函数声明 int rand_int_100(); void test1(); void test2(); int main() { cout << "测试1: \n"; test1(); cout << "\n测试2: \n"; test2(); } // 函数实现 // 输出容器对象c中的元素 template <typename T> void output(const T &c) { for(auto &i: c) cout << i << " "; cout << endl; } // 返回[0, 100]区间内的一个随机整数 int rand_int_100() { return rand() % 101; } // 测试1 // 对容器类对象指定迭代器区间进行赋值、排序 void test1() { vector<int> v0(10); // 创建一个动态数组对象v0, 对象大小为10 generate(v0.begin(), v0.end(), rand_int_100); // 产生[0, 100]之间的随机整数赋值给指定迭代器区间[v0.begin(), v0.end())内的每个数据项 cout << "v0: "; output(v0); vector<int> v1{v0}; sort(v1.begin(), v1.end()); // 对指定迭代器区间[v1.begin(), v1.end())内数据项进行升序排序 cout << "v1: "; output(v1); vector<int> v2{v0}; sort(v2.begin()+1, v2.end()-1); // 对指定迭代器区间[v1.begin()+1,v1.end()-1)内数据项进行升序排序 cout << "v2: "; output(v2); } // 测试2 // 对容器类对象指定迭代器区间进行赋值、计算最大值/最小值/均值 void test2() { vector<int> v0(10); generate(v0.begin(), v0.end(), rand_int_100); cout << "v0: "; output(v0); auto iter1 = min_element(v0.begin(), v0.end()); cout << "最小值: " << *iter1 << endl; auto iter2 = max_element(v0.begin(), v0.end()); cout << "最大值: " << *iter2 << endl; auto ans = minmax_element(v0.begin(), v0.end()); cout << "最小值: " << *(ans.first) << endl; cout << "最大值: " << *(ans.second) << endl; double avg1 = accumulate(v0.begin(), v0.end(), 0)/v0.size(); cout << "均值: " << fixed << setprecision(2) << avg1 << endl; cout << endl; vector<int> v1{v0}; cout << "v0: "; output(v0); sort(v1.begin(), v1.end()); double avg2 = accumulate(v1.begin()+1, v1.end()-1, 0)/(v1.size()-2); cout << "去掉最大值、最小值之后，均值: " << avg2 << endl; }
实验结果：
task3 实验代码：
#include <iostream> #include <string> #include <algorithm> bool is_palindrome(std::string s); int main() { using namespace std; string s; while(cin >> s) // 多组输入，直到按下Ctrl+Z后结束测试 cout << boolalpha << is_palindrome(s) << endl; } bool is_palindrome(std::string s){ int left=0; int right=s.length() -1; while(left<right){ if(s[left]!=s[right]) return false; else left++; right--; } return true; }
实验结果：
task4 实验代码:
#include <iostream> #include <string> #include <algorithm> std::string dec2n(int x, int n = 2); int main() { using namespace std; int x; while(cin >> x) { cout << "十进制: " << x << endl; cout << "二进制: " << dec2n(x) << endl; cout << "八进制: " << dec2n(x, 8) << endl; cout << "十六进制: " << dec2n(x, 16) << endl << endl; } } std::string dec2n(int x, int n ){ std::string a="0123456789ABCDEF"; std::string result; int remainder; if(x==0) return "0"; while(x>0){ remainder= x % n; result=a[remainder]+result; x=x/n; } return result; }
实验结果:
task5 实验代码:
#include<iostream> #include<string> #include<vector> #include<algorithm> using namespace std; template <typename T> void output(const T &c); void test1(); int main(){ test1(); } template <typename T> void output(const T &c){ for(auto &i:c) cout<<i<<" "; cout <<endl; } void test1(){ vector<string> v0{"a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"}; cout<<" "; output(v0); vector<string> v1{"A","B","C","D","E","G","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"}; for(int i=1;i<=26;i++){ if(i<=9) cout<<" "; rotate(v1.begin(),v1.begin()+1,v1.end()); cout<<i<<" "; output(v1); } }
实验结果:
task6 实验代码:
#include <iostream> #include <vector> #include <string> #include <algorithm> #include <numeric> #include <iomanip> using namespace std; void problem(); int main(){ srand(time(0)); problem(); } void problem(){ int correctcount = 0; for(int i=1;i<=10;i++){ int a = rand()%10 + 1; int b = rand()%10 + 1; int answer; char op; switch(rand()%4){ case 0: op='+'; answer = a+b; break; case 1: op='-'; a = rand()%10 + 1; b = rand()%a; answer = a-b; break; case 2: op='*'; answer = a*b; break; case 3: op='/'; a = rand()%10 + 1; b = (rand()%a)+1; answer = a/b; break; } cout<<a<<" "<<op<<" "<<b<<" "<<"="; int useranswer; cin>>useranswer; if(useranswer=answer){ correctcount++; } } double accuracy=static_cast<double>(correctcount)/10*100; cout<<"正确率:"<<fixed<<setprecision(2)<<accuracy<<"%"<<endl; }
实验结果:
