var n,i,max,min,l:integer;
a: array [1..100] of integer;
begin
readln(n);
l:=0;

for i:=1 to n do
read(a[i]);
for i:=1 to n do
begin
if a[i]<a[i+1] then l:=l+(a[i+1]-a[i]);
if a[i]>=a[i+1] then begin
if l>max then
max:=l;
l:=0;
end;
end;

writeln(max);
readln;
end.