set terminal png
set output "2-12.png"
set size 0.6, 0.6
set ylabel "Blocking Ratio(%)"
set xlabel "Bandwidth Requirment"
set yrange [0:100]
set xrange [0:20]
set xtics 0, 5, 20
set ytics 0, 20, 100
set key right bottom box
#set title ""
plot "2-12.txt" using 1:2 title 'p=0.6' w linesp 1, '' using 1:3 title 'p=0.7' w linesp 2, '' using 1:4 title 'p=0.8' w linesp 3