module no1801_1850.no1816;

import std;

void main() {
    int N;
    readf("%d\n", N);

    auto A = readln.chomp.split.to!(long[]);

    auto heap = A.heapify;
    int cnt;
    while (heap.length > 1) {
        long x = heap.front;
        heap.popFront;

        long y = heap.front;
        heap.popFront;

        heap.insert(cnt % 2 == 0 ? x * y : (x + y - 1) / y);
        ++cnt;
    }

    heap.front.writeln;
}