A practical introduction to Pascal programming language - GIARA

Data structuresExercise 4.22. Create a program that reads a string and draws it as a left-based pyramid. Forexample, the word computer must look like:croemtpu□This program consists of writing, at line i, the i-th char of the string preceded by a givennumber of blank spaces. The key is being able to summarize such number in a single formula, sothat the program becomes readable. In this case, such formula is min(i-1,length(str)-1. Notethat by finding out the expression we avoid using extra alternative constructions to discriminatebetween the first and the last half of the string.Program 103: Exercise 4.22program c04e22;uses math;constN=15;varstr:STRING[N];i,j:integer;begin(* Reading the text *)write(’Please input the string of, at most, ’,N,’ chars: ’);readln(str);(* Writing the matrix *)for i:=1 to length(str) dobeginfor j:=1 to min(i-1,length(str)-i) dowrite(’ ’);writeln(str[i])endend.⊡Exercise 4.23. Create a program that reads a string and draws it as an upside down pyramid.For example, the word computer must look like:computer□In order to display this structure we have to realize that, between each pair of chars, we needto put blank spaces. Hence, again it becomes a problem of epitomizing the number of blankspaces depending upon the number of the row we are in. First, we have to decide how manyblank spaces must be written before the first char, and then how many before the second. On87