aqi = read.csv(file = "C:/Users/stan/Desktop/205410185/1.csv",
               header = T, sep = ",")
colnames(aqi) = c("date", "AQI",
                  "PM10","PM2.5")
ui = fluidPage(
  titlePanel('AIR'),
  sidebarLayout(
    sidebarPanel( selectizeInput("AIR",
                   "Select Contaminant:",
                   choices = c("AQI",
                               "PM2.5",
                               "10"),
                   selected = "AQI",
                   multiple = TRUE )
  ),

    mainPanel(
      plotOutput("plot")
    )
  )
server = function(input, output) {

  output$plot = renderPlot({
    ggplot(aqi) +
      geom_line(mapping = aes(x = date, y = aqi[,input$AIR], colour = input$AIR)) +
      labs (x = "date", y = "aqi", title = "AIR") +
      scale_colour_discrete(name = "AIR")
  })
}
shinyApp(ui, server)