diff --git a/level1/p07_encrypt_decrypt/encrypt_decrypt.cpp b/level1/p07_encrypt_decrypt/encrypt_decrypt.cpp
new file mode 100644
index 00000000..190fd60e
--- /dev/null
+++ b/level1/p07_encrypt_decrypt/encrypt_decrypt.cpp
@@ -0,0 +1,46 @@
+#include <stdio.h>
+#include <string.h>
+#include <iostream>
+
+void encrypt(char* source, char* encrypted)
+{
+	while (*source != '\0')
+	{
+		*encrypted = 158 - *source;
+		source++;
+		encrypted++;
+	}
+}
+
+void decrypt(char* encrypted, char* source)
+{
+	while (*encrypted != '\0')
+	{
+		*source = 158 - *encrypted;
+		source++;
+		encrypted++;
+	}
+}
+
+int main()
+{
+	printf("请输入需要加密字符串的长度：");
+	int n = 0;
+	std::cin >> n;
+	char* a = new char[n + 1]();
+	char* b = new char[n + 1]();
+	scanf("%s", a);
+	encrypt(a, b);
+	printf("加密后的字符串为：");
+	printf("%s\n", b);
+	printf("请输入需要解密的字符串的长度：");
+	int s = 0;
+	scanf("%d", &s);
+	char* c = new char[n + 1]();
+	char* d = new char[n + 1]();
+	printf("需要解密的字符串为：");
+	scanf("%s", c);
+	decrypt(c, d);
+	printf("解密后的字符串为：");
+	printf("%s", d);
+}
\ No newline at end of file