set terminal png
set xtics; set ytics;
set grid xtics
set grid ytics
set output "keysize_time.png"
set title "Time complexity for various key sizes"
set xlabel "key size (in bytes)"
set ylabel "time (miliseconds)"
plot "keysize_time.dat" using 1:2 title "key generation time" with linespoints, "keysize_time.dat" using 1:3 title "encryption time" with linespoints, "keysize_time.dat" using 1:4 title "decryption time" with linespoints
