program Project2;

{$APPTYPE CONSOLE}

var
s,n:integer;
f1,f2:text;
begin
assign(f1,'input.txt');
reset(f1);
s:=0;
while not(eof(f1)) do
begin
readln(f1,n);
s:=s+n;
end;
close(f1);
assign(f2,'output.txt');
rewrite(f2);
writeln(f2,s);
close(f2);
end.