diff --git a/2207/C语言同步练习源码/2.循环结构-7.c b/2207/C语言同步练习源码/2.循环结构-7.c
new file mode 100644
index 0000000..3080245
--- /dev/null
+++ b/2207/C语言同步练习源码/2.循环结构-7.c
@@ -0,0 +1,16 @@
+#include <stdio.h>
+
+int main(){
+	
+	int month, total = 2, i;
+	scanf("%d", &month);
+
+	for(i=1;i<=month;i++){
+		if(i%3==0){
+			total *= 2;
+		}
+		printf("%d��:%d����\n", i, total); 
+	}
+
+	return 0;
+}
diff --git a/2207/C语言同步练习答案.md b/2207/C语言同步练习答案.md
index d9045c9..56e2a32 100644
--- a/2207/C语言同步练习答案.md
+++ b/2207/C语言同步练习答案.md
@@ -338,6 +338,22 @@ int main(){
 ![image-20250220231022607](https://yp.smallkun.cn/markdown/image-20250220231022607.png!compress)
 
 ```c
+#include <stdio.h>
+
+int main(){
+	
+	int month, total = 2, i;
+	scanf("%d", &month);
+
+	for(i=1;i<=month;i++){
+		if(i%3==0){
+			total *= 2;
+		}
+		printf("%d月:%d个数\n", i, total); 
+	}
+
+	return 0;
+}
 ```
 
 ### 循环结构-8