adjusting the color to grayscale

i have the following code, which generates bar graphs. i want to set the colors of all the leftbars to one color,all middle bars to another color and the right bar to a separate color. and i want them to be in grayscale,can anyone help me out

leftBarCenter  = 5;
rightBarCenter = 10;
leftBarCenter1 = 15;
rightBarCenter1 = 20;
leftBarCenter2 = 25;
rightBarCenter2 = 30;
leftBarCenter3 = 35;
rightBarCenter3 = 40;
leftBarCenter4 = 45;
rightBarCenter4 = 50;
desiredWidth = 7;
figure;%(1)
bar([leftBarCenter rightBarCenter leftBarCenter1  rightBarCenter1 leftBarCenter2  rightBarCenter2 leftBarCenter3  rightBarCenter3 leftBarCenter4 rightBarCenter4],[success success1 success2 success3 success4 success5 success6 success7 success8 success9 ]);
xlabel('Fspl,Rician,Rayleigh')
ylabel('Success')
axis([0 80 0 120])
title('Success Probability of BPSK,QPSK,16-QPSK,16-QAM & 64-QAM')