How to tidy the date format and solve the overlapping problem in x-axis

Hi there, I am facing two issues about the following data set. Can you please help me for reordering date format and solving the overlapping problem about the name of x-axis, thanks!

library(ggplot2)
library(tibble)
count_date1  <- tribble(~Date, ~freq,
                       "28-06-2015", 27,
                        "29-04-2015", 22,
                        "29-05-2015", 14,
                        "29-06-2015", 51,
                       "30-04-2015", 24,
                       "30-05-2015", 9,
                       "30-06-2015",   53,
                       "31-05-2015",   10,
                         "4/1/2015", 18,
                         "4/10/2015", 21,
                         "4/11/2015", 5,
                        "4/12/2015", 15)

ggplot(count_date1, aes(Date,freq)) + 
    geom_point() + 
    geom_line(aes(group=Date)) +
    xlab("Date") + 
    ylab("No. of Complaints")

^{Created on 2020-08-13 by the reprex package (v0.3.0)}

Session info

``` r devtools::session_info() #> - Session info --------------------------------------------------------------- #> setting value #> version R version 4.0.0 (2020-04-24) #> os Windows 10 x64 #> system x86_64, mingw32 #> ui RTerm #> language (EN) #> collate English_United Kingdom.1252 #> ctype English_United Kingdom.1252 #> tz Australia/Sydney #> date 2020-08-13 #> #> - Packages ------------------------------------------------------------------- #> ! package * version date lib source #> assertthat 0.2.1 2019-03-21 [1] CRAN (R 4.0.0) #> backports 1.1.6 2020-04-05 [1] CRAN (R 4.0.0) #> callr 3.4.3 2020-03-28 [1] CRAN (R 4.0.0) #> cli 2.0.2 2020-02-28 [1] CRAN (R 4.0.0) #> crayon 1.3.4 2017-09-16 [1] CRAN (R 4.0.0) #> desc 1.2.0 2018-05-01 [1] CRAN (R 4.0.0) #> devtools 2.3.0 2020-04-10 [1] CRAN (R 4.0.0) #> digest 0.6.25 2020-02-23 [1] CRAN (R 4.0.0) #> ellipsis 0.3.0 2019-09-20 [1] CRAN (R 4.0.0) #> evaluate 0.14 2019-05-28 [1] CRAN (R 4.0.0) #> fansi 0.4.1 2020-01-08 [1] CRAN (R 4.0.0) #> fs 1.4.1 2020-04-04 [1] CRAN (R 4.0.0) #> D glue 1.4.1 2020-05-13 [1] CRAN (R 4.0.0) #> highr 0.8 2019-03-20 [1] CRAN (R 4.0.0) #> htmltools 0.4.0 2019-10-04 [1] CRAN (R 4.0.0) #> knitr 1.28 2020-02-06 [1] CRAN (R 4.0.0) #> magrittr 1.5 2014-11-22 [1] CRAN (R 4.0.0) #> memoise 1.1.0 2017-04-21 [1] CRAN (R 4.0.0) #> pkgbuild 1.0.8 2020-05-07 [1] CRAN (R 4.0.0) #> pkgload 1.0.2 2018-10-29 [1] CRAN (R 4.0.0) #> prettyunits 1.1.1 2020-01-24 [1] CRAN (R 4.0.0) #> processx 3.4.2 2020-02-09 [1] CRAN (R 4.0.0) #> ps 1.3.3 2020-05-08 [1] CRAN (R 4.0.0) #> R6 2.4.1 2019-11-12 [1] CRAN (R 4.0.0) #> Rcpp 1.0.4.6 2020-04-09 [1] CRAN (R 4.0.0) #> remotes 2.1.1 2020-02-15 [1] CRAN (R 4.0.0) #> rlang 0.4.6 2020-05-02 [1] CRAN (R 4.0.0) #> rmarkdown 2.2 2020-05-31 [1] CRAN (R 4.0.0) #> rprojroot 1.3-2 2018-01-03 [1] CRAN (R 4.0.0) #> sessioninfo 1.1.1 2018-11-05 [1] CRAN (R 4.0.0) #> stringi 1.4.6 2020-02-17 [1] CRAN (R 4.0.0) #> stringr 1.4.0 2019-02-10 [1] CRAN (R 4.0.0) #> testthat 2.3.2 2020-03-02 [1] CRAN (R 4.0.0) #> usethis 1.6.1 2020-04-29 [1] CRAN (R 4.0.0) #> withr 2.2.0 2020-04-20 [1] CRAN (R 4.0.0) #> xfun 0.14 2020-05-20 [1] CRAN (R 4.0.0) #> yaml 2.2.1 2020-02-01 [1] CRAN (R 4.0.0) #> #> [1] C:/Users/Phyllis/OneDrive/Documents/R/win-library/4.0 #> [2] C:/Program Files/R/R-4.0.0/library #> #> D -- DLL MD5 mismatch, broken installation. ```

etc5523-2020 / exercise2C

How to tidy the date format and solve the overlapping problem in x-axis #21