diff --git a/day8/homework/h1.cpp b/day8/homework/h1.cpp
new file mode 100644
index 0000000..96b01c5
--- /dev/null
+++ b/day8/homework/h1.cpp
@@ -0,0 +1,23 @@
+// 输入一个整数 n，然后输入 n 个整数，输出它们的平均值。
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n, sum = 0;
+    int nums[100];
+    cout << "请输入整数 n: ";
+    cin >> n;
+    int n_copy = n;
+
+    cout << "请输入 " << n << " 个整数: ";
+    while (--n >= 0)
+    {
+        cin >> nums[n];
+        sum += nums[n];
+    }
+
+    cout << "平均值为：" << sum / n_copy << endl;
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h10.cpp b/day8/homework/h10.cpp
new file mode 100644
index 0000000..f0cd51a
--- /dev/null
+++ b/day8/homework/h10.cpp
@@ -0,0 +1,50 @@
+// 输入一个整数 n，然后输入 n 个整数，输出其中所有质数的个数。
+#include <iostream>
+
+using namespace std;
+
+bool isPrime(int num)
+{
+    if (num <= 1) // 1 不是质数
+        return false;
+
+    int i = 2;
+    while (i * i <= num)
+    {
+        if (num % i == 0)
+            return false;
+        else
+            i++;
+    }
+
+    return true;
+}
+
+int main()
+{
+    int n;
+    int *nums = new int[n];
+    int i = 0;
+    int cnt = 0; // 计数器
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+        i++;
+    }
+
+    while (--n >= 0)
+    {
+        if (isPrime(nums[n]) == true)
+            cnt++;
+        else
+            continue;
+    }
+
+    cout << "输入的整数中所有质数的个数为: " << cnt << endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h11.cpp b/day8/homework/h11.cpp
new file mode 100644
index 0000000..0eff65e
--- /dev/null
+++ b/day8/homework/h11.cpp
@@ -0,0 +1,33 @@
+// 输入一个整数 n，然后输入 n 个整数，输出其中所有能被 3 整除的数的个数。
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n;
+    int *nums = new int[n];
+    int i = 0;
+    int cnt = 0; // 计数器
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+        i++;
+    }
+
+    while (--n >= 0)
+    {
+        if (nums[n] % 3 == 0)
+            cnt++;
+        else
+            continue;
+    }
+
+    cout << "输入的整数中所有能被 3 整除的数的个数: " << cnt << endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h12.cpp b/day8/homework/h12.cpp
new file mode 100644
index 0000000..fe3c5b2
--- /dev/null
+++ b/day8/homework/h12.cpp
@@ -0,0 +1,33 @@
+// 输入一个整数 n，然后输入 n 个整数，输出其中所有能被 5 整除的数的个数。
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n;
+    int *nums = new int[n];
+    int i = 0;
+    int cnt = 0; // 计数器
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+        i++;
+    }
+
+    while (--n >= 0)
+    {
+        if (nums[n] % 5 == 0)
+            cnt++;
+        else
+            continue;
+    }
+
+    cout << "输入的整数中所有能被 5 整除的数的个数: " << cnt << endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h13.cpp b/day8/homework/h13.cpp
new file mode 100644
index 0000000..6e6889d
--- /dev/null
+++ b/day8/homework/h13.cpp
@@ -0,0 +1,33 @@
+// 输入一个整数 n，然后输入 n 个整数，输出其中所有能被 7 整除的数的个数。
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n;
+    int *nums = new int[n];
+    int i = 0;
+    int cnt = 0; // 计数器
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+        i++;
+    }
+
+    while (--n >= 0)
+    {
+        if (nums[n] % 7 == 0)
+            cnt++;
+        else
+            continue;
+    }
+
+    cout << "输入的整数中所有能被 7 整除的数的个数: " << cnt << endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h14.cpp b/day8/homework/h14.cpp
new file mode 100644
index 0000000..3dbafcf
--- /dev/null
+++ b/day8/homework/h14.cpp
@@ -0,0 +1,33 @@
+// 输入一个整数 n，然后输入 n 个整数，输出其中所有能被 3 和 5 整除的数的个数。
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n;
+    int *nums = new int[n];
+    int i = 0;
+    int cnt = 0; // 计数器
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+        i++;
+    }
+
+    while (--n >= 0)
+    {
+        if (nums[n] % 3 == 0 && nums[n] % 5 == 0)
+            cnt++;
+        else
+            continue;
+    }
+
+    cout << "输入的整数中所有能被 3 和 5 整除的数的个数: " << cnt << endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h15.cpp b/day8/homework/h15.cpp
new file mode 100644
index 0000000..0c68817
--- /dev/null
+++ b/day8/homework/h15.cpp
@@ -0,0 +1,33 @@
+// 输入一个整数 n，然后输入 n 个整数，输出其中所有能被 3 或 5 整除的数的个数。
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n;
+    int *nums = new int[n];
+    int i = 0;
+    int cnt = 0; // 计数器
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+        i++;
+    }
+
+    while (--n >= 0)
+    {
+        if (nums[n] % 3 == 0 || nums[n] % 5 == 0)
+            cnt++;
+        else
+            continue;
+    }
+
+    cout << "输入的整数中所有能被 3 或 5 整除的数的个数: " << cnt << endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h16.cpp b/day8/homework/h16.cpp
new file mode 100644
index 0000000..f13adf6
--- /dev/null
+++ b/day8/homework/h16.cpp
@@ -0,0 +1,35 @@
+// 输入一个整数 n，然后输入 n 个整数，输出其中所有能被 3 或 5 但不能被同时整除的数的个数。
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n;
+    int *nums = new int[n];
+    int i = 0;
+    int cnt = 0; // 计数器
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+        i++;
+    }
+
+    while (--n >= 0)
+    {
+        if (nums[n] % 3 == 0 && nums[n] % 5 == 0)
+            continue;
+        else if (nums[n] % 3 == 0 || nums[n] % 5 == 0)
+            cnt++;
+        else
+            continue;
+    }
+
+    cout << "输入的整数中所有能被 3 或 5 但不能被同时整除的数的个数: " << cnt << endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h17.cpp b/day8/homework/h17.cpp
new file mode 100644
index 0000000..75bc8c8
--- /dev/null
+++ b/day8/homework/h17.cpp
@@ -0,0 +1,33 @@
+// 输入一个整数 n，然后输入 n 个整数，输出其中所有能被  3 或 5 整除的数的和。
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n;
+    int *nums = new int[n];
+    int i = 0;
+    int cnt = 0; // 计数器
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+        i++;
+    }
+
+    while (--n >= 0)
+    {
+        if (nums[n] % 3 == 0 || nums[n] % 5 == 0)
+            cnt += nums[n];
+        else
+            continue;
+    }
+
+    cout << "输入的整数中所有能被  3 或 5 整除的数的和: " << cnt << endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h18.cpp b/day8/homework/h18.cpp
new file mode 100644
index 0000000..08213ff
--- /dev/null
+++ b/day8/homework/h18.cpp
@@ -0,0 +1,35 @@
+// 输入一个整数 n，然后输入 n 个整数，输出其中所有能被 3 或 5 但不能被同时整除的数的和。
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n;
+    int *nums = new int[n];
+    int i = 0;
+    int cnt = 0; // 计数器
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+        i++;
+    }
+
+    while (--n >= 0)
+    {
+        if (nums[n] % 3 == 0 && nums[n] % 5 == 0)
+            continue;
+        else if (nums[n] % 3 == 0 || nums[n] % 5 == 0)
+            cnt += nums[n];
+        else
+            continue;
+    }
+
+    cout << "输入的整数中所有能被 3 或 5 但不能被同时整除的数的和: " << cnt << endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h19.cpp b/day8/homework/h19.cpp
new file mode 100644
index 0000000..a86bb54
--- /dev/null
+++ b/day8/homework/h19.cpp
@@ -0,0 +1,38 @@
+// 输入一个整数 n，然后输入 n 个整数，输出其中所有能被 3 或 5 整除的数的平均值。
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n;
+    int *nums = new int[n];
+    int i = 0;
+    int sum = 0; // 和
+    int cnt = 0; // 计数器
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+        i++;
+    }
+
+    while (--n >= 0)
+    {
+        if (nums[n] % 3 == 0 || nums[n] % 5 == 0)
+        {
+
+            cnt++;
+            sum += nums[n];
+        }
+        else
+            continue;
+    }
+
+    cout << "输入的整数中所有能被 3 或 5 整除的数的平均值: " << sum / (double)cnt << endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h1_2.cpp b/day8/homework/h1_2.cpp
new file mode 100644
index 0000000..0b076c5
--- /dev/null
+++ b/day8/homework/h1_2.cpp
@@ -0,0 +1,25 @@
+// 输入一个整数 n，然后输入 n 个整数，输出它们的平均值。
+// 方法 2
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n;
+    double avg = 0;
+    int nums[100];
+    cout << "请输入整数 n: ";
+    cin >> n;
+    int n_copy = n;
+
+    cout << "请输入 " << n << " 个整数: ";
+    while (--n >= 0)
+    {
+        cin >> nums[n];
+        avg += nums[n] / (double)n_copy;
+    }
+
+    cout << "平均值为：" << avg << endl;
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h1_3.cpp b/day8/homework/h1_3.cpp
new file mode 100644
index 0000000..cba31bc
--- /dev/null
+++ b/day8/homework/h1_3.cpp
@@ -0,0 +1,28 @@
+// 输入一个整数 n，然后输入 n 个整数，输出它们的平均值。
+// 方法 3
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n;
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    int *nums = new int[n];
+    double avg = 0.0;
+    int i = 0;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+        avg += nums[i] / (double)n;
+        i++;
+    }
+
+    cout << "平均值为：" << avg << endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h2.cpp b/day8/homework/h2.cpp
new file mode 100644
index 0000000..5de3810
--- /dev/null
+++ b/day8/homework/h2.cpp
@@ -0,0 +1,34 @@
+// 输入一个整数 n，然后输入 n 个整数，输出它们的最大值和最小值。
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n;
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    int *nums = new int[n];
+    int max = nums[0], min = nums[0];
+    int i = 0;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+
+        if (max < nums[i])
+            max = nums[i];
+
+        if (min > nums[i])
+            min = nums[i];
+
+        i++;
+    }
+
+    cout << "最大值为: " << max << ",\t"
+         << "最小值为: " << min << endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h20.cpp b/day8/homework/h20.cpp
new file mode 100644
index 0000000..6236b54
--- /dev/null
+++ b/day8/homework/h20.cpp
@@ -0,0 +1,39 @@
+// 输入一个整数 n，然后输入 n 个整数，输出其中所有能被 3 或 5 但不能被同时整除的数的平均值。
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n;
+    int *nums = new int[n];
+    int i = 0;
+    int sum = 0; // 和
+    int cnt = 0; // 计数器
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+        i++;
+    }
+
+    while (--n >= 0)
+    {
+        if (nums[n] % 3 == 0 && nums[n] % 5 == 0)
+            continue;
+        else if (nums[n] % 3 == 0 || nums[n] % 5 == 0)
+        {
+            cnt++;
+            sum += nums[n];
+        }
+        else
+            continue;
+    }
+
+    cout << "输入的整数中所有能被 3 或 5 但不能被同时整除的数的平均值: " << sum / (double)cnt << endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h3.cpp b/day8/homework/h3.cpp
new file mode 100644
index 0000000..2fdbe3c
--- /dev/null
+++ b/day8/homework/h3.cpp
@@ -0,0 +1,52 @@
+// 输入一个整数 n，然后输入 n 个整数，将它们按从小到大的顺序排序，并输出排序后的结果。
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n;
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    int *nums = new int[n];
+    int i = 0;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+        i++;
+    }
+
+    cout << "排序前的结果: ";
+    for (int i = 0; i < n; i++)
+    {
+        cout << nums[i] << " ";
+    }
+
+    for (int i = 0; i < n - 1; i++)
+    {
+        for (int j = 0; j < n - i - 1; j++)
+        {
+            if (nums[j] > nums[j + 1])
+            {
+                /* int temp = nums[i];
+                nums[i] = nums[i + 1];
+                nums[i + 1] = temp; */
+
+                nums[j] = nums[j] ^ nums[j + 1];
+                nums[j + 1] = nums[j] ^ nums[j + 1];
+                nums[j] = nums[j] ^ nums[j + 1];
+            }
+        }
+    }
+
+    cout << "从小到大排序后的结果: ";
+    for (int i = 0; i < n; i++)
+    {
+        cout << nums[i] << " ";
+    }
+
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h4.cpp b/day8/homework/h4.cpp
new file mode 100644
index 0000000..1f1b0ef
--- /dev/null
+++ b/day8/homework/h4.cpp
@@ -0,0 +1,49 @@
+// 输入一个整数 n，然后输入 n 个整数，将它们按从大到小的顺序排序，并输出排序后的结果。
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n;
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    int *nums = new int[n];
+    int i = 0;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+        i++;
+    }
+
+    cout << "排序前的结果: ";
+    for (int i = 0; i < n; i++)
+    {
+        cout << nums[i] << "\t";
+    }
+    cout << endl;
+
+    for (int i = 0; i < n - 1; i++)
+    {
+        for (int j = 0; j < n - i - 1; j++)
+        {
+            if (nums[j] < nums[j + 1])
+            {
+                nums[j] = nums[j] ^ nums[j + 1];
+                nums[j + 1] = nums[j] ^ nums[j + 1];
+                nums[j] = nums[j] ^ nums[j + 1];
+            }
+        }
+    }
+
+    cout << "从大到小排序后的结果: ";
+    for (int i = 0; i < n; i++)
+    {
+        cout << nums[i] << "\t";
+    }
+
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h5.cpp b/day8/homework/h5.cpp
new file mode 100644
index 0000000..410fbd1
--- /dev/null
+++ b/day8/homework/h5.cpp
@@ -0,0 +1,30 @@
+// 输入一个整数 n，然后输入 n 个整数，输出其中所有奇数的和。
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n;
+    int *nums = new int[n];
+    int i = 0;
+    int sum = 0;
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+        i++;
+    }
+
+    while (--n >= 0)
+    {
+        if (nums[n] % 2 == 1)
+            sum += nums[n];
+    }
+    cout << "输入的整数中所有奇数的和为: " << sum << endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h6.cpp b/day8/homework/h6.cpp
new file mode 100644
index 0000000..8c62f36
--- /dev/null
+++ b/day8/homework/h6.cpp
@@ -0,0 +1,30 @@
+// 输入一个整数 n，然后输入 n 个整数，输出其中所有偶数的和。
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n;
+    int *nums = new int[n];
+    int i = 0;
+    int sum = 0;
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+        i++;
+    }
+
+    while (--n >= 0)
+    {
+        if (nums[n] % 2 == 0)
+            sum += nums[n];
+    }
+    cout << "输入的整数中所有偶数的和为: " << sum << endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h7.cpp b/day8/homework/h7.cpp
new file mode 100644
index 0000000..0fc8ec4
--- /dev/null
+++ b/day8/homework/h7.cpp
@@ -0,0 +1,30 @@
+// 输入一个整数 n，然后输入 n 个整数，输出其中所有正数的和。
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n;
+    int *nums = new int[n];
+    int i = 0;
+    int sum = 0;
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+        i++;
+    }
+
+    while (--n >= 0)
+    {
+        if (nums[n] > 0)
+            sum += nums[n];
+    }
+    cout << "输入的整数中所有正数的和为: " << sum << endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h8.cpp b/day8/homework/h8.cpp
new file mode 100644
index 0000000..af0094b
--- /dev/null
+++ b/day8/homework/h8.cpp
@@ -0,0 +1,30 @@
+// 输入一个整数 n，然后输入 n 个整数，输出其中所有负数的和。
+#include <iostream>
+
+using namespace std;
+
+int main()
+{
+    int n;
+    int *nums = new int[n];
+    int i = 0;
+    int sum = 0;
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+        i++;
+    }
+
+    while (--n >= 0)
+    {
+        if (nums[n] < 0)
+            sum += nums[n];
+    }
+    cout << "输入的整数中所有负数的和为: " << sum << endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/day8/homework/h9.cpp b/day8/homework/h9.cpp
new file mode 100644
index 0000000..b1d85ef
--- /dev/null
+++ b/day8/homework/h9.cpp
@@ -0,0 +1,50 @@
+// 输入一个整数 n，然后输入 n 个整数，输出其中所有素数的个数。
+#include <iostream>
+
+using namespace std;
+
+bool isPrime(int num)
+{
+    if (num <= 1) // 1 不是质数
+        return false;
+
+    int i = 2;
+    while (i * i <= num)
+    {
+        if (num % i == 0)
+            return false;
+        else
+            i++;
+    }
+
+    return true;
+}
+
+int main()
+{
+    int n;
+    int *nums = new int[n];
+    int i = 0;
+    int cnt = 0; // 计数器
+    cout << "请输入整数 n: ";
+    cin >> n;
+
+    cout << "请输入" << n << "个整数: ";
+    while (i < n)
+    {
+        cin >> nums[i];
+        i++;
+    }
+
+    while (--n >= 0)
+    {
+        if (isPrime(nums[n]) == true)
+            cnt++;
+        else
+            continue;
+    }
+
+    cout << "输入的整数中所有素数的个数为: " << cnt << endl;
+
+    return 0;
+}
\ No newline at end of file