program infoflip;
var n, m,c,j,i,i2 :longint;
var s :int64;
var a :array[1..100,1..100] of integer;
var f,ff :text;
begin
assign(f,'flip.in');
reset(f);
read(f,n); readln(f,m);
for c:=1 to n do
begin
for i:=1 to m do
begin
read(f,a[c,i]);
end;
readln(f);
end;
close(f);
s:=0;
for j:=1 to n do
begin
for i2:=1 to m do
begin
if a[j,i2]>0 then
s:=s+a[j,i2];
end;
end;
assign(ff,'flip.out');
rewrite(ff);
write(ff,s);
close(ff)
end.