sorry i have a question what's the meaning of int and max? got confuse with the computation.

waittime = 360;
if(activity >= 15)
        waittime = (int)(90 - activity);
if(activity >= 60)
        waittime=(int)(34.7586 - (0.0793103 * activity));
if(activity >= 100)
        waittime = max((int)(14-(activity/50)), 4);