a.
Var i : integer;
S : real;
Begin
S:= 0;
For i:=1 to 100 do S:= S + i;
Write (S);
Readln;
End.
b.
Var i : integer;
S : real;
Begin
S:= 0;
For i:=1 to 10 do S:= S + 1/i;
Write (S);
Readln;
End.
c.
Var i,n : integer;
S : real;
Begin
write ('n = '); read (n);
S:= 0;
For i:=1 to n do S:= S + i;
Write (S);
Readln;
End.
d.
Var i : integer;
S : real;
Begin
write ('n = '); read (n);
S:= 0;
For i:=1 to n do S:= S + 1/i;
Write (S);
Readln;
End.