import std.algorithm;
import std.array;
import std.container;
import std.conv;
import std.math;
import std.range;
import std.stdio;
import std.string;
import std.typecons;

T read(T)() { return readln.chomp.to!T; }
T[] reads(T)() { return readln.split.to!(T[]); }
alias readint = read!int;
alias readints = reads!int;

void main() {
    auto q = new BinaryHeap!(Array!int);

    string s;
    while ((s = readln.chomp).length > 0) {
        if (s == "end")
            break;

        if (s[0] == 'e') { // extract
            writeln(q.front);
            q.popFront;
        }
        else {
            auto ss = s.split;
            int x = ss[1].to!int;
            q.insert(x);
        }
    }
}

