V2 MaxWindow

function max(a: int, b: int) -> int {
    if (a > b) { return a; }
    return b;
}

struct Window {
    mv: int,
    l: int[],
    r: int[],
    function push(self: Window, x: int) {
        self.r.push(x);
        self.mv = max(self.mv, x);
    }
    function pop(self: Window) {
        if (self.l.length() == 0) {
            let mx = -2000000007;
            while (self.r.length() > 0) {
                mx = max(mx, self.r[self.r.length() - 1]);
                self.l.push(mx);
                self.r.pop();
            }
            self.mv = -2000000007;
        }
        self.l.pop();
    }
    function get(self: Window) -> int {
        let res = self.mv;
        if (self.l.length() > 0) { res = max(res, self.l[self.l.length() - 1]); }
        return res;
    }
}