Color repetition when using boxes in gnuplot - gnuplot

Question

My data file has just two columns.The following MWE on those columns produces boxes with repeated colors. Is it possible to produce unique colors for each box?
reset
set term postscript eps size 5.5,4.5 enhanced color solid lw 2\
font "arial,28"
set key right
set xtics rotate -45 font ",20"
set style fill solid 1 border -1
plot 'rankdefcount.dat' using ($0):2:($0):xticlabels(1) \
notitle w boxes lc variable
quit
Here is the output I got:

Answer 1

After few attempts and help from the SO experts, I came up with the following solutions; none of them perfect, though.
Solution 1: ( with a random repetition using rand and rgb calls)
reset
set term postscript eps size 5.5,4.5 enhanced color solid lw 2 font \
"arial,28"
set key right
rgb(r,g,b)=int(255*r)*65536+int(255*g)*256+int(255*b)
do for [i=1:31] {
myrand=rand(int(rand(0)*i*100)+i*100)
set style line i linecolor rgb rgb(rand(0),rand(0),rand(0))
}
set xtics rotate -45 font ",20"
set style fill solid 1 border -1
plot 'rankdefcount.dat' using ($0):2:($0):xticlabels(1) \
notitle w boxes lc variable
quit
Here is the corresponding output:
With palette definition (solution 2):
reset
set term postscript eps size 5.5,4.5 enhanced color solid lw 2 font \
"arial,28"
set key right
set palette color model HSV
set palette defined (0 0 1 1,1 1 1 1)
set palette defined ( 0 0 1 0, 1 0 1 1, 6 0.8333 1 1, 7 0.8333 0 1)
set boxwidth 0.5
unset colorbox
set xtics rotate -45 font ",20"
set style fill solid 1 border -1
plot 'rankdefcount.dat' using ($0):2:($0):xticlabels(1) \
notitle w boxes lc palette
quit
This is the output:
For another solution (solution 3), replace the definition above with the following lines:
set palette color model HSV
set pm3d explicit at b
set palette rgbformulae 3, 2, 2
This is what I got:

Answer 2

You may try and redefine as much linetypes as boxes you want to show. The code should go before the plot.
colors="black red orange #fa8072 ...." #[as much colors as needed]
do for [L=1:words(colors)]{
set linetype L lc rgb word(colors,L)
}
You can find colors for gnuplot here.
http://www.uni-hamburg.de/Wiss/FB/15/Sustainability/schneider/gnuplot/colors.htm