实验一
实验任务1：
// 现代C++标准库、算法库体验
// 本例用到以下内容:
// 1. 字符串string, 动态数组容器类vector、迭代器
// 2. 算法库：反转元素次序、旋转元素
// 3. 函数模板、const引用作为形参
#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()); // 反转指定迭代器区间的元素
cout << "s1 = " << s1 << endl;
string s2{s0};
reverse_copy(s0.begin(), s0.end(), s2.begin()); // 将指定迭代区间的元素拷贝到指定迭代器开始的目标区间，并且在复制过程中反转次序
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()); // 旋转指定迭代器区间[v1.begin(), v1.end())之间的数据项，旋转后从迭代器v1.begin()+1位置的数据项开始
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);
}
实验任务2：
#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;
}
实验任务3：
#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){
std::string t{s};
reverse(s.begin(),s.end());
if(s==t)
return true;
else
return false;
}
实验任务4：
#include <iostream>
#include <string>
#include <algorithm>
#include<vector>
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) {
if (x == 0)
{
std::string a;
a = char(48);
return a;
}
int num;
std::vector<char> vec;
while (x != 0) {
num = x % n;
x = x / n;
if (num == 10)
vec.insert(vec.begin(),num + 55);
else if (num == 11)
vec.insert(vec.begin(), num + 55);
else if (num == 12)
vec.insert(vec.begin(), num + 55);
else if (num == 13)
vec.insert(vec.begin(), num + 55);
else if (num == 14)
vec.insert(vec.begin(), num + 55);
else if (num == 15)
vec.insert(vec.begin(), num + 55);
else
vec.insert(vec.begin(), num + 48);
}
std::string s;
for (auto i : vec) {
s = s + i;
}
return s;
}
实验任务5：
#include<iostream>
#include<string>
#include<vector>
#include<iomanip>
using namespace std;
int main() {
vector<char> vec1;
vector<char> vec2;
vector<char> vec3;
for (char i = 'A'; i <= 'Z'; ++i) {
vec1.push_back(i);
}
for (char i = 'a'; i <= 'z'; ++i) {
vec2.push_back(i);
}
cout <<" ";
for (auto i : vec2) {
cout << setw(2) << i;
}
cout << endl;
for (int i = 1; i <= 26; i++) {
rotate(vec1.begin(), vec1.begin() + 1, vec1.end());
cout << setw(2) << i;
for (auto i : vec1) {
cout << setw(2) << i;
}
cout << endl;
}
}
实验任务6：
#include<iostream>
#include<vector>
#include<random>
#include<iomanip>
using namespace std;
int main() {
vector<int> v1{ 0,1,2,3,4,5,6,7,8,9,10 };
vector<char> v2{'+','-','*','/'};
//创建随机数引擎
random_device rd;
mt19937 gen(rd());
uniform_int_distribution<> dist1(0, v1.size() - 1);
uniform_int_distribution<> dist2(0, v2.size() - 1);
int N = 10;
int a,c;
char b;
double correct = 0;
while (N--) {
int random_num1 = dist1(gen);
int random_num2 = dist2(gen);
a = v1[random_num1];
b = v2[random_num2];
cout << v1[random_num1] << setw(2) << v2[random_num2];
random_num1 = dist1(gen);
while (random_num1 == 0 && random_num2 == 3) {
random_num1 = dist1(gen);
}
while (a < v1[random_num1]&&random_num2==1) {
random_num1 = dist1(gen);
}
cout << setw(2) << v1[random_num1] << setw(2) << "==";
int c;
cin >> c;
int ans=0;
if (random_num2 == 0)
ans = a + random_num1;
else if(random_num2 == 1)
ans = a - random_num1;
else if (random_num2 == 2)
ans = a * random_num1;
else if (random_num2 == 3)
ans = a / random_num1;
if (c == ans)
++correct;
}
cout << "正确率：" <<fixed << setprecision(2) << correct *10 << "%";
}
