Problem:
Score : 200 points

Problem Statement

Given N integers A_1, ..., A_N, compute A_1 \times ... \times A_N.

However, if the result exceeds 10^{18}, print -1 instead.

Constraints

2 \leq N \leq 10^5

0 \leq A_i \leq 10^{18}

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N
A_1 ... A_N

Output

Print the value A_1 \times ... \times A_N as an integer, or -1 if the value exceeds 10^{18}.

Sample Input 1

2
1000000000 1000000000

Sample Output 1

1000000000000000000

We have 1000000000 \times 1000000000 = 1000000000000000000.

Sample Input 2

3
101 9901 999999000001

Sample Output 2

-1

We have 101 \times 9901 \times 999999000001 = 1000000000000000001, which exceeds 10^{18}, so we should print -1 instead.

Sample Input 3

31
4 1 5 9 2 6 5 3 5 8 9 7 9 3 2 3 8 4 6 2 6 4 3 3 8 3 2 7 9 5 0

Sample Output 3

0

Solution in Pascal (FPC 3.0.4) (judge verdict: Runtime Error)

program hi;
var 
    ans: QWord;
    a: array[1..10010] of QWord;
    n, i, j: integer;

procedure swap(var x: QWord; var y: QWord);
var tmp: QWord;
begin
    tmp := x;
    x := y;
    y := tmp;
end;

begin
    readln(n);
    ans := 1;
    for i := 1 to n do 
        read(a[i]);
    for i := 1 to n - 1 do
        for j := 1 to n - 1 do 
            if a[j] > a[j + 1] then
                swap(a[j], a[j + 1]);
    for i := 1 to n do begin
        if a[i] = 0 then begin
            writeln(0);
            exit;
        end;
        if ans <= 1000000000000000000 div a[i] then 
            ans := ans * a[i]
        else begin
            writeln(-1);
            exit;
        end;
    end;
    writeln(ans);
end.