sidebarLayout(
  sidebarPanel,
  mainPanel,
  position = c("left", "right"),
  fluid = TRUE
)

sidebarPanel(..., width = 4)

mainPanel(..., width = 8)

## Only run examples in interactive R sessions
if (interactive()) {
options(device.ask.default = FALSE)

# Define UI
ui <- fluidPage(

  # Application title
  titlePanel("Hello Shiny!"),

  sidebarLayout(

    # Sidebar with a slider input
    sidebarPanel(
      sliderInput("obs",
                  "Number of observations:",
                  min = 0,
                  max = 1000,
                  value = 500)
    ),

    # Show a plot of the generated distribution
    mainPanel(
      plotOutput("distPlot")
    )
  )
)

# Server logic
server <- function(input, output) {
  output$distPlot <- renderPlot({
    hist(rnorm(input$obs))
  })
}

# Complete app with UI and server components
shinyApp(ui, server)
}