set terminal png
set output 'fibgr.png'
set grid
set style data linespoints
set title "Calculation of 10000 Fibonacci numbers (Fn)"

set xlabel "Approximate number n"
set ylabel "Time, s"

plot "benchmark.txt" using 1:2 with lines title 'iterative', \
     "benchmark.txt" using 1:3 with lines title 'matrix'