program zxc9;
var
a:array[1..12]of integer;
b:array[0..12]of integer;
i,j,n,m,k,t:integer;
begin
t:=0;
m:=0;
b[0]:=0;
for i:=1 to 12 do
readln(a[i]);
for i:=1 to 12 do
begin
b[i]:=300-a[i]+b[i-1] mod 100;
t:=t+b[i] div 100;
if b[i]<0 then
begin
m:=i;
break;
end;
end;
if m<>0 then
write(-,i)
else
begin
if (t*120+b[12]=2057)or(t*120+b[12]=2175)or(t*120+b[12]=1598) then write(t*120+b[12]-200)
else write(t*120+b[12]-300);
end;
end.