#this program shows how to work with 2-dimensional lists

import random
ROW = 3
COL = 4


	
def sumave(scores, sizeRow, sizeCol):
	#this function returns sum and average
	#of all elements in 2 dim list
	
	sum =0
	for i in range(sizeRow):
		for j in range(sizeCol):
			sum = sum + scores[i][j]

	average = float(sum)/(sizeRow*sizeCol)
	return sum, average

	

def main():
	#definition of the 2-dim list

	scores=[[0,0,0,0], [0,0,0,0], [0,0,0,0]]
	print(scores)
	
	#assignig random values to 2-dim list
	for i in range(ROW):
		for j in range(COL):
			scores[i][j]=random.randint(1,5)

	print("after assigning random values")
	print(scores)	
	print("how to print a matrix ")
	for i in range(ROW):
		print(scores[i])
	
	print("all elements in in one column")
	for i in range(ROW):
        	for j in range(COL):

			print(scores[i][j]) 	
	
	print("sum and average of all elements")
	sum, average=sumave(scores, ROW, COL)
	print(sum, average)	
main()