A practical introduction to Pascal programming language - GIARA

Iterative constructions3.4.3 On-screen matrix displayingThis problems consists of creating in the command line some sort of mosaic dependent uponsome value introduced by the user. Mostly, their resolution lies on finding out an expression ableto represent the information to be displayed at every position of the matrix. If such expression isfound, we only have the need of using a double for statement to go through rows and columns.Exercise 3.31. Create a program that reads an integer N from the keyboard and writes a matrixof N × N elements so that at each position (i, j) the value i · j is displayed. That is, a matrix suchas1 2 3 . . . N2 4 6 . . . 2 · N3 6 9 . . . 3 · N. . . . . . . . . . . . . . .N 2 · N 3 · N . . . N 2□In this case the expression to be applied at each position is simply i · j, where i representsthe number of row and j the number of column. Note that we must write each cell with thecommand write, so that we stay in the same line until we finish each row.Program 71: Exercise 3.31program c03e31;varn:integer;i,j:integer;beginwrite(’Please input the value of n: ’);readln(n);for i:=1 to n dobeginfor j:=1 to n dowrite(’ ’,i*j:4,’ ’);writelnendend.⊡Exercise 3.32. Create a program that reads an integer N from the keyboard and writes a matrixof N × N elements so that at each position (i, j) the Manhattan distance to the main diagonal.That is, a matrix such as0 1 2 . . . N1 0 1 . . . N − 12 1 0 . . . N − 2 .. . . . . . . . . . . . . . .N N − 1 N − 2 . . . 0□The distance to the main diagonal is always the either the distance in horizontal or the distancein vertical (it is always the same). Hence, at each position (i, j) we must display either |i − j| or|j − i|.61