a1 = [0,3,13, 28, 49, 75, 110];
a2 = [0,3, 12, 27, 47, 77, 108,152];
a3 = [0,0,0,0,0,0,0,0];
a4 = [0, 8, 31, 73, 131, 205, 296, 405];
b = [1,10000,20000,30000,40000,50000,60000];
v = [1,10000,20000,30000,40000,50000,60000,70000];
plot(b,a1,v,a2,v,a3,v,a4);
legend('recursive selection sort', 'iterative selection sort', 'quicksort','bubble sort');