如何在ggplot2中创建带有多个计数变量的线状图？

install.packages("ggplot2")
library(ggplot2)

df <- data.frame(category = c("A", "B", "C", "D"),
                 count1 = c(10, 15, 8, 12),
                 count2 = c(5, 9, 6, 10),
                 count3 = c(7, 11, 9, 13))

library(tidyr)
df_long <- gather(df, key = "variable", value = "value", -category)

ggplot(df_long, aes(x = category, y = value, color = variable)) +
  geom_line()

ggplot(df_long, aes(x = category, y = value, color = variable)) +
  geom_line() +
  labs(title = "Line Chart with Multiple Count Variables",
       x = "Category",
       y = "Count") +
  theme_minimal()