Just another update

Task/Standard-deviation/Pascal/standard-deviation.pascal

@@ -0,0 +1,28 @@
+program stddev;
+uses math;
+const
+  n=8;
+var
+  arr: array[1..n] of real =(2,4,4,4,5,5,7,9);
+function stddev(n: integer): real;
+var
+   i: integer;
+   s1,s2,variance,x: real;
+begin
+    for i:=1 to n do
+    begin
+      x:=arr[i];
+      s1:=s1+power(x,2);
+      s2:=s2+x
+    end;
+    variance:=((n*s1)-(power(s2,2)))/(power(n,2));
+    stddev:=sqrt(variance)
+end;
+var
+   i: integer;
+begin
+    for i:=1 to n do
+    begin
+      writeln(i,' item=',arr[i]:2:0,' stddev=',stddev(i):18:15)
+    end
+end.