m = matrix(sample(c(0:30), 100, replace = TRUE), 10)
print(m)
# run:
#
# [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
# [1,] 7 10 27 5 29 21 24 11 10 20
# [2,] 16 0 12 13 8 19 2 20 1 4
# [3,] 9 23 8 23 14 10 1 27 20 10
# [4,] 4 28 22 14 2 21 7 25 9 6
# [5,] 27 12 6 0 22 12 3 26 25 7
# [6,] 21 22 3 18 23 15 19 11 3 4
# [7,] 23 9 18 15 9 17 26 23 16 5
# [8,] 28 7 14 20 30 21 7 28 4 7
# [9,] 10 18 13 3 9 6 26 12 0 22
# [10,] 4 12 7 10 9 23 27 23 28 25
#