Data update

Task/Prime-decomposition/Pascal-P/prime-decomposition.pas

@@ -0,0 +1,47 @@
+program primdecomp(input, output);
+  (* Prime decomposition *)
+const
+  maxfacindex = 30;
+  (* -(2^31) has most prime factors (31 twos) than other 32-bit signed integer.
+  *)
+type
+  tfacs = array[0 .. maxfacindex] of integer;
+var
+  i, n, cnt: integer;
+  facs: tfacs;
+
+  function facscnt(n: integer; var facs: tfacs): integer;
+  var
+    i, cnt: integer;
+  begin
+    n := abs(n);
+    cnt := 0;
+    if n >= 2 then
+    begin
+      i := 2;
+      while i * i <= n do
+      begin
+        if n mod i = 0 then
+        begin
+          n := n div i;
+          facs[cnt] := i;
+          cnt := cnt + 1;
+          i := 2;
+        end
+        else
+          i := i + 1;
+      end;
+      facs[cnt] := n;
+      cnt := cnt + 1;
+    end;
+    facscnt := cnt;
+  end;
+
+begin
+  write('Enter a number: ');
+  read(n);
+  cnt := facscnt(n, facs);
+  for i := 0 to cnt - 2 do write(facs[i]:1, ' ');
+  writeln(facs[cnt - 1]:1);
+  (* readln; *)
+end.