diff --git a/level1/p01_running_letter/1-p01.c b/level1/p01_running_letter/1-p01.c
new file mode 100644
index 0000000..1be0349
--- /dev/null
+++ b/level1/p01_running_letter/1-p01.c
@@ -0,0 +1,39 @@
+#include <stdio.h>
+#include <unistd.h>
+
+void move_letter(char letter, float speed) {
+    int position = 0;
+    int direction = 1;  // 1表示向右移动，-1表示向左移动
+
+    while (1) {
+        // 清空控制台输出
+        printf("\033c");
+
+        // 输出字母前的空格
+        for (int i = 0; i < position; ++i) {
+            printf(" ");
+        }
+
+        // 输出字母
+        printf("%c\n", letter);
+
+        // 停顿一段时间
+        usleep(speed * 1000000);
+
+        // 根据方向和位置更新下一个位置
+        position += direction;
+
+        // 检查是否到达边界，如果是则改变方向
+        if (position >= 79 - 1) {  // 79是典型控制台窗口宽度，减去1是为了避免边界溢出
+            direction = -1;
+        } else if (position <= 0) {
+            direction = 1;
+        }
+    }
+}
+
+// 调用函数进行测试，传入要移动的字母和速度（单位为秒）
+int main() {
+    move_letter('A', 0.1);
+    return 0;
+}
\ No newline at end of file
diff --git a/level1/p01_running_letter/main.c b/level1/p01_running_letter/main.c
deleted file mode 100644
index f84d224..0000000
--- a/level1/p01_running_letter/main.c
+++ /dev/null
@@ -1,6 +0,0 @@
-#include <printf.h>
-
-int main() {
-    printf("hello world!\n");
-    return 0;
-}
\ No newline at end of file