round(((27 + 28 + 28)/ 3)返回27 ?! (C / C ++)


avg = round(r + g + b) / 3);

r = avg;
g = avg;
b = avg;

It should do the grayscale image effect. There are no syntax errors, but apperently avg, when calculated as shown above with values r as 27, and both g and b as 28, avg finds it to be 27. I know it is 27.66666... and when rounded that is 28. if you can either-or/both explain to me why this happens with round(), and/or give me a solution, it is really appreciated. thanks!