任务1:
task1.cpp
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 }
运行测试截图
任务2：
task2.cpp
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 }
运行测试截图
任务3：
task3.cpp
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 bool is_palindrome(std::string s){
16 std::string m{s};
17 reverse (m.begin(),m.end());
18 return s==m;
19 }
运行测试截图
任务4：
task4.cpp
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 std::string dec2n(int x, int n ) {
20 std::string s;
21 int a;
22 do {
23 a = x % n;
24 if (a < 10)s += a + '0';
25 else s += 'A' + (a - 10);
26 x /= n;
27 } while (x != 0);
28 std::reverse(s.begin(), s.end());
29 return s;
30 }
运行测试截图
任务5：
task5.cpp
1 #include<iostream>
2 #include<string>
3 #include<algorithm>
4 #include<iomanip>
5 #include<vector>
6
7 using namespace std;
8
9 template<typename T>
10 void output(const T& c);
11
12 int main() {
13 string s;
14 cout << " ";
15 for (int j = 0; j <= 25; j++) {
16 s = j + 'a';
17
18 cout << setw(2) << s;
19 }
20 cout << endl;
21 vector<int>v0{ 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25 };
22 for (int i = 0; i <= 25; i++) {
23 vector<int>vi{ v0 };
24 int k=i+1;
25 rotate(vi.begin(), vi.begin() + k, vi.end());
26 cout << setw(2) << i+1;
27 output(vi);
28 cout << endl;
29 }
30
31 }
32 template<typename T>
33 void output(const T& c) {
34 for (auto& i : c) {
35 string m;
36 m = i + 'A';
37 cout << setw(2)<< m;
38 }
39 }
运行测试截图
任务6：
task6.cpp
1 #include<iostream>
2 #include<algorithm>
3 #include<iomanip>
4 #include<vector>
5 #include<string>
6 #include<cstdlib>
7
8 using namespace std;
9
10 int rand_int_10(int x = 11);
11
12 int rand_int(int y);
13
14 int main() {
15 int q = 0;
16 for (int i = 0; i < 10; i++) {
17 int x, y, z;
18 string m;
19 vector<string>s{ "+","-","*","/" };
20 int random_index = rand() % s.size();
21 if (random_index == 1) {
22 x = rand_int_10();
23 y = rand_int_10(x);
24 }
25 else if (random_index == 3) {
26 x = rand_int_10();
27 y = rand_int(x);
28
29 }
30 else {
31 x = rand_int_10();
32 y = rand_int_10();
33 }
34 m = s[random_index];
35 cout << x << setw(2) << m << setw(2) << y << setw(2) << "=";
36 cin >> z;
37 switch (random_index) {
38 case 0:
39 if (z == x + y) q += 10;
40 break;
41 case 1:
42 if (z == x - y) q += 10;
43 break;
44 case 2:
45 if (z == x * y) q += 10;
46 break;
47 case 3:
48 if (z == x / y)q += 10;
49 break;
50 }
51
52
53 }
54 cout << "正确率:" << setprecision(2) << q << "%" << endl;
55 }
56
57 int rand_int_10(int x) {
58 return (rand() % (x - 1)) + 1;
59 }
60
61 int rand_int(int y) {
62 int m = y;
63 vector<int>e2{ 1,2 };
64 vector<int>e3{ 1,3 };
65 vector<int>e4{ 1,2,4 };
66 vector<int>e5{ 1,5 };
67 vector<int>e6{ 1,2,3,6 };
68 vector<int>e7{ 1,7 };
69 vector<int>e8{ 1,2,4,8 };
70 vector<int>e9{ 1,3,9 };
71 vector<int>e10{ 1,2,5,10 };
72 switch (m) {
73 case 1:m = 1;
74 break;
75 case 2:
76 m = e2[rand() % e2.size()];
77
78 break;
79 case 3:
80 m = e3[rand() % e3.size()];
81 break;
82 case 4:
83 m = e4[rand() % e4.size()];
84 break;
85 case 5:
86 m = e5[rand() % e5.size()];
87 break;
88 case 6:
89 m = e6[rand() % e6.size()];
90 break;
91 case 7:
92 m = e7[rand() % e7.size()];
93 break;
94 case 8:
95 m = e8[rand() % e8.size()];
96 break;
97 case 9:
98 m = e9[rand() % e9.size()];
99 break;
100 case 10:
101 m = e10[rand() % e10.size()];
102 break;
103
104
105
106
107 }
108 return m;
109 }
运行测试截图
