如何计算项目在数组中的次数

I've decided to just try again from the start since I'm a bit more awake now and go over building this step by step. i've looked at some of the answers and there seems to be many ways one could go about this. I'm trying to do this using what I've learned so far. I've learned about variables, basic functions, objects, arrays, 'this' and the push method. I know for, while, do while, for in loops, though the for loop is the one I understand the best.I've decided to just try again from the start s