var n,k,m,z,i,j:integer;
    a:array[1..69,1..69]of longint;
{function sum(a,b:integer):integer;
var i,j:integer;
begin
for i:=1 to a do
       }
begin
read(n,m);
k:=-1;
for i:=1 to n do
        for j:=1 to m do read(a[i,j]);
for i:=1 to n do begin
        z:=0;
        for j:=1 to n do
               if a[i,j]>0 then z:=a[i,j]+z;
end;
write(z);
end.