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*(*
procedure triangle(x1,x2,y1,y2,z1,z2 : integer);
begin
line(x1,x2,y1,y2);
line(y1,y2,z1,z2);
line(z1,z2,x1,x2);
end;
Then just put some coordinates in and .......
use:
-----
program test;
uses
crt, graph;
var
gd, gm : integer;
{the procedure has to be here}
begin
gd:=detect;
initgraph(gd,gm,'');
if graphresult <> grok then halt(1);
triangle(100,200,300,400,50,50);
readln;
closegraph;
end.
-------
I think the original post was asking for a program to generate Pascal's Triangle.
Pascal's Triangle is a classic example of a recurrence relation that arranges
the binomial coefficients into the shape of a triangle. The binomial coefficients
are a set of ordered coefficients of the terms in an expansion of a power of a
binomial. For example:
Binomial Expanded Coefficients
-----------------------------------------------------------------
(a+b)^0 1 1
(a+b)^1 a + b 1,1
(a+b)^2 a^2 + 2ab + b^2 1,2,1
(a+b)^3 a^3 + 3(a^2)b + 3a(b^2) + b^3 1,3,3,1
Here is the top of Pascal's Triangle:
1
1 1
1 2 1
1 3 3 1
1 4 6 4 1
1 5 10 10 5 1
.
.
.
Note that each position of the triangle holds the sum of the two elements
diagonally above it. If the positions of each row of the triangle are
0..n (from left to right) where n is the number of the current row, then
the coefficient values C(row,position) in each position are calculated as
follows:
C(n,0) = 1 and C(n,n) = 1 For n >= 0
C(n,k) = C(n-1,k) + C(n-1,k-1) For n > k > 0
Since each row of the triangle is dependent on the row immediately above it,
this lends itself nicely to a recursive algorithm:
*)
***FUNCTION **CalcCoefficient(**CONST **n : Integer; **CONST **k : integer ) : Integer;
**BEGIN
IF **(k=0) **or **(k=n)
**THEN
**result := 1
**ELSE
**result := CalcCoefficient( n-1, k ) + CalcCoefficient( n-1, k-1 );
**END**;
**PROCEDURE **GenerateTriangle( **CONST **maxOrder : INTEGER );
**VAR
**currentCoefficient : Integer;
order : integer;
term : integer;
**BEGIN
FOR **order := 0 **TO **maxOrder **DO
FOR **term := 0 **TO **order **DO
BEGIN
**currentCoefficient := CalcCoefficient( order, term );
*{ now store, or print the current coefficient - whatever you want }
***END**;
**END**;
Note, recursion, **as is **often he **case**, **is not **the most efficient way **to **generate
**Pascal**'s Triangle. In this case, each row of the triangle is calculated repeatedl
**for **every higher order row. This wastes a trememdous amount **of **processing.

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