实验1：
1 // 现代C++标准库、算法库体验
2 // 本例用到以下内容:
3 // 1. 字符串string, 动态数组容器类vector、迭代器
4 // 2. 算法库：反转元素次序、旋转元素
5 // 3. 函数模板、const引用作为形参
6
7 #include <iostream>
8 #include <string>
9 #include <vector>
10 #include <algorithm>
11
12 using namespace std;
13
14 // 声明
15 // 模板函数声明
16 template<typename T>
17 void output(const T &c);
18
19 // 普通函数声明
20 void test1();
21 void test2();
22 void test3();
23
24 int main() {
25 cout << "测试1: \n";
26 test1();
27
28 cout << "\n测试2: \n";
29 test2();
30
31 cout << "\n测试3: \n";
32 test3();
33 }
34
35 // 函数实现
36 // 输出容器对象c中的元素
37 template <typename T>
38 void output(const T &c) {
39 for(auto &i: c)
40 cout << i << " ";
41 cout << endl;
42 }
43
44 // 测试1
45 // 组合使用算法库、迭代器、string反转字符串
46 void test1() {
47 string s0{"0123456789"};
48 cout << "s0 = " << s0 << endl;
49
50 string s1{s0};
51 reverse(s1.begin(), s1.end()); // 反转指定迭代器区间的元素
52 cout << "s1 = " << s1 << endl;
53
54 string s2{s0};
55 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
56 cout << "s2 = " << s2 << endl;
57 }
58
59 // 测试2
60 // 组合使用算法库、迭代器、vector反转动态数组对象vector内数据
61 void test2() {
62 vector<int> v0{2, 0, 4, 9};
63 cout << "v0: ";
64 output(v0);
65
66 vector<int> v1{v0};
67 reverse(v1.begin(), v1.end());
68 cout << "v1: ";
69 output(v1);
70
71 vector<int> v2{v0};
72 reverse_copy(v0.begin(), v0.end(), v2.begin());
73 cout << "v2: ";
74 output(v2);
75 }
76
77 // 测试3
78 // 组合使用算法库、迭代器、vector实现元素旋转移位
79 void test3() {
80 vector<int> v0{0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
81 cout << "v0: ";
82 output(v0);
83
84 vector<int> v1{v0};
85 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
86 cout << "v1: ";
87 output(v1);
88
89 vector<int> v2{v0};
90 rotate(v2.begin(), v2.begin()+2, v2.end());
91 cout << "v2: ";
92 output(v2);
93
94 vector<int> v3{v0};
95 rotate(v3.begin(), v3.end()-1, v3.end());
96 cout << "v3: ";
97 output(v3);
98
99 vector<int> v4{v0};
100 rotate(v4.begin(), v4.end()-2, v4.end());
101 cout << "v4: ";
102 output(v4);
103 }
运行结果
实验2：
1 #include <iostream>
2 #include <vector>
3 #include <string>
4 #include <algorithm>
5 #include <numeric>
6 #include <iomanip>
7
8 using namespace std;
9
10 // 函数声明
11 // 模板函数声明
12 template<typename T>
13 void output(const T &c);
14
15 // 普通函数声明
16 int rand_int_100();
17 void test1();
18 void test2();
19
20 int main() {
21 cout << "测试1: \n";
22 test1();
23
24 cout << "\n测试2: \n";
25 test2();
26 }
27
28 // 函数实现
29 // 输出容器对象c中的元素
30 template <typename T>
31 void output(const T &c) {
32 for(auto &i: c)
33 cout << i << " ";
34 cout << endl;
35 }
36
37 // 返回[0, 100]区间内的一个随机整数
38 int rand_int_100() {
39 return rand() % 101;
40 }
41
42 // 测试1
43 // 对容器类对象指定迭代器区间进行赋值、排序
44 void test1() {
45 vector<int> v0(10); // 创建一个动态数组对象v0, 对象大小为10
46 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
47 cout << "v0: ";
48 output(v0);
49
50 vector<int> v1{v0};
51 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
52 cout << "v1: ";
53 output(v1);
54
55 vector<int> v2{v0};
56 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
57 cout << "v2: ";
58 output(v2);
59 }
60
61 // 测试2
62 // 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
63 void test2() {
64 vector<int> v0(10);
65 generate(v0.begin(), v0.end(), rand_int_100);
66 cout << "v0: ";
67 output(v0);
68
69 auto iter1 = min_element(v0.begin(), v0.end());
70 cout << "最小值: " << *iter1 << endl;
71
72 auto iter2 = max_element(v0.begin(), v0.end());
73 cout << "最大值: " << *iter2 << endl;
74
75 auto ans = minmax_element(v0.begin(), v0.end());
76 cout << "最小值: " << *(ans.first) << endl;
77 cout << "最大值: " << *(ans.second) << endl;
78 double avg1 = accumulate(v0.begin(), v0.end(), 0)/v0.size();
79 cout << "均值: " << fixed << setprecision(2) << avg1 << endl;
80
81 cout << endl;
82
83 vector<int> v1{v0};
84 cout << "v0: ";
85 output(v0);
86 sort(v1.begin(), v1.end());
87 double avg2 = accumulate(v1.begin()+1, v1.end()-1, 0)/(v1.size()-2);
88 cout << "去掉最大值、最小值之后，均值: " << avg2 << endl;
89 }
运行结果
实验3：
1 #include <iostream>
2 #include <string>
3 #include <algorithm>
4
5 bool is_palindrome(std::string s);
6
7 int main() {
8 using namespace std;
9 string s;
10
11 while(cin >> s) // 多组输入，直到按下Ctrl+Z后结束测试
12 cout << boolalpha << is_palindrome(s) << endl;
13 }
14
15 // 函数is_palindrom定义
16 // 待补足
17 // ×××
18 bool is_palindrome(const std::string s) {
19 std::string a = s;
20
21 std::reverse(a.begin(), a.end());
22
23 return s == a;
24 }
运行结果
实验4：
1 #include <iostream>
2 #include <string>
3 #include <algorithm>
4
5 std::string dec2n(int x, int n = 2);
6
7 int main() {
8 using namespace std;
9
10 int x;
11 while(cin >> x) {
12 cout << "十进制: " << x << endl;
13 cout << "二进制: " << dec2n(x) << endl;
14 cout << "八进制: " << dec2n(x, 8) << endl;
15 cout << "十六进制: " << dec2n(x, 16) << endl << endl;
16 }
17 }
18
19 // 函数dec2n定义
20 // 待补足
21 // ×××
22 std::string dec2n(int x, int n ) {
23 if (x == 0) return "0";
24
25 std::string result;
26 const char digits[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
27
28 while (x > 0) {
29 int remainder = x % n;
30 result += digits[remainder];
31 x /= n;
32 }
33
34 std::reverse(result.begin(), result.end());
35
36 return result;
37 }
38
运行结果：
实验5：
1 #include <iostream>
2 #include <string>
3 #include <algorithm>
4 #include <iomanip>
5 using namespace std;
6 int main(){
7 cout<<setw(2)<<" ";
8 std::string a="abcdefghijklmnopqrstuvwxyz";
9 std::string b="ABCDEFGHIJKLMNOPQRETUVWXYZABCDEFGHIJKLMNOPQRETUVWXYZ";
10 for( int i=0;i<a.size();i++){
11 cout<<setw(2)<<a[i];
12 }
13 cout<<endl;
14 for(int high=1;high<=a.size();high++){
15 int s;
16 cout<<setw(2)<<high;
17 for(int wide=0;wide<a.size();wide++){
18 s=high+wide;
19 if(wide+high>a.size()){
20 s=wide+high-26;
21 }
22 cout<<setw(2)<<b[s];
23 }
24 cout<<endl;
25 }
26 }
运行结果
实验6：
1 #include <iostream>
2 #include <string>
3 #include <algorithm>
4 #include <cmath>
5 #include <ctime>
6 #include <iomanip>
7 #include <cstdlib>
8
9 using namespace std;
10
11 int main() {
12 srand(time(0));
13 const int Q = 10;
14 int A = 0;
15
16 for (int i = 0; i < Q; ++i) {
17 int num1 = rand() % 10 + 1;
18 int num2 = rand() % 10 + 1;
19 char operators[] = {'+', '-', '*', '/'};
20 char op = operators[rand() % 4];
21
22
23 if (op == '-') {
24
25 while (num1 <= num2) {
26 num1 = rand() % 10 + 1;
27 num2 = rand() % 10 + 1;
28 }
29 } else if (op == '/') {
30
31 while (num1 % num2 != 0) {
32 num1 = rand() % 10 + 1;
33 num2 = rand() % (num1 / 2) + 1;
34
35 }
36 }
37
38
39 int correctResult;
40 switch (op) {
41 case '+': correctResult = num1 + num2; break;
42 case '-': correctResult = num1 - num2; break;
43 case '*': correctResult = num1 * num2; break;
44 case '/': correctResult = num1 / num2; break;
45 }
46 cout << num1 << " " << op << " " << num2 << " = ";
47 int userAnswer;
48 cin >> userAnswer;
49
50
51 if (userAnswer == correctResult) {
52 ++A;
53 }
54 }
55
56
57 double accuracy = static_cast<double>(A) / Q * 100;
58 cout << fixed << setprecision(2) << "正确率: " << accuracy << "%" << endl;
59
60 return 0;
61 }
62
运行结果
标签：begin,初体验,cout,int,编程,c++,v0,v1,include From： https://www.cnblogs.com/hinaou/p/18453510