合成数列の和 (Pascal)

合成数列の和	https://qiita.com/advent-calendar/2018/composite-number
Python(/Ruby)	https://qiita.com/cielavenir/items/dcbd839b0c66af1bc971
Crystal	https://qiita.com/cielavenir/items/1a0dd1a94aca9935f5aa
Kuin	https://qiita.com/cielavenir/items/47fd18fc68055d990599
Swift	https://qiita.com/cielavenir/items/6cde3b20866c842dc9e2
Kotlin	https://qiita.com/cielavenir/items/f58eaa30f90781229a6d
Pascal	https://qiita.com/cielavenir/items/35c2fc54ca16b620c9c7

composite.pas

program composite;
var i,s,n,cnt: longint;

function isqrt(n: longint): longint;
var
	x: longint;
	y: longint;
begin
	if(n<=0) then
		isqrt:=0
	else if(n<4) then
		isqrt:=1
	else begin
		x:=0;
		y:=n;
		while((x<>y) and (x+1<>y)) do begin
			x:=y;
			y:=(n div y+y) div 2;
		end;
		isqrt:=x;
	end;
end;

function isPrime(i: longint): boolean;
var
	j: longint;
begin
	isPrime:=true;
	if i<2 then isPrime:=false;
	for j:=2 to isqrt(i) do begin
		if(i mod j < 1) then
			isPrime:=false;
	end;
end;

begin
	read(n);
	i:=2;
	cnt:=0;
	s:=0;
	while(cnt<n) do begin
		if(not isPrime(i)) then begin
			s:=s + i;
			cnt:=cnt + 1;
		end;
		i:=i + 1;
	end;
	writeln(s);
end.