R- combining two list of values into a data frame: error arguments imply differing number of rows: : I have two lists that I would like to combine into a dataframe. The lists follows this basic logic: 

    list1<-list("A", "C", "B")
    list2<-list(c("la la", "po sdfejn kfgndñflgn"), "characther(0)", c("4   5","baby", "yeah")) # note that characther(0) means that there is no data
   The outcome I want is like this:

    output <- data.frame( V1 = c(rep("A",3), "C", rep("B",3)), V2 = c(1,2,3, NA, 4,5,6))
 
   I have used codes that I have seen in this page such as: ```solution1 <- do.call(rbind, Map(data.frame, a = list1, b= list2))```as I often do. This code works for the example. However, I obtain the following error message when I use this formula for the large lists I am working on, : 
     
    Error in (function (..., row.names = NULL, check.rows = FALSE, check.names = 
    TRUE,  : arguments imply differing number of rows: 1, 0
      
   I have tried to ```unlist(list1), unlist(list1)``` but it does not work. If both list are identical, where is really the source of problem and how can I solve in order to have the desired output? 

