在某个区域内对多维数组中的元素求和

I am creating a game where a robot traverses a map that is a 2D array. Each spot in the 2D array has a "treasure" that is a number of coins. I want to be able to add all the elements up to 4 places up, down, right, and left from the robots current position (making a "plus" sign). So, if we have an array:I am creating a game where a robot traverses a