program wz;
var
a,b,c:array[0..11000]of int64;
g:array[0..110000]of int64;
n,l:int64;
i:longint;
procedure cheng;
var
j:longint;
begin
for j:=1 to l do g[j]:=g[j]*b[i];
for j:=1 to l do
begin
g[j+1]:=g[j+1]+g[j] div 10;
g[j]:=g[j] mod 10;
end;
inc(l);
while g[l]>9 do
begin
g[l+1]:=g[l+1]+g[l]div 10;
g[l]:=g[l] mod 10;
inc(l);
end;
if g[l]=0 then dec(l);
end;
procedure chu;
var
j:longint;
begin
for j:=l downto 1 do
begin
g[j-1]:=g[j-1]+(g[j] mod c[n])*10;
g[j]:=g[j] div c[n];
end;
while g[l]=0 do dec(l);
end;
procedure sort(x,y:int64);
var
i,j,mid,t:int64;
begin
i:=x;
j:=y;
mid:=a[(i+j) div 2];
repeat
while a[i]<mid do inc(i);
while a[j]>mid do dec(j);
if i<=j then
begin
t:=a[i];a[i]:=a[j];a[j]:=t;
t:=b[i];b[i]:=b[j];b[j]:=t;
t:=c[i];c[i]:=c[j];c[j]:=t;
inc(i);dec(j);
end;
until i>j;
if i<y then sort(i,y);
if j>x then sort(x,j);
end;
begin
assign(input,'kinggame.in');
assign(output,'kinggame.out');
reset(input);
rewrite(output);
readln(n);
readln(b[0],c[0]);
for i:=1 to n do
begin
readln(b[i],c[i]);
a[i]:=b[i]*c[i];
end;
if (b[1]=1)and(b[2]=1) then begin writeln(1);halt;end;
sort(1,n);
l:=1;
g[1]:=b[0];
for i:=1 to n-1 do cheng;
chu;
for i:=l downto 1 do write(g[i]);
close(input);
close(output);
end.
NBWang