#include <iostream>
#define int long long

int s[999999], to = 0, ta = 0, n, inp, x;
signed main() {
    std::cin >> n;
    for (int i = 0; i < n; i++) {
        std::cin >> inp;
        if (inp == 0) {
            std::cin >> x;
            s[++ta] = x;
        } else if (inp == 1) {
            if (to == ta--) break;
        } else {
            int m = 0;
            for (int i = to + 1; i <= ta; i++) {
                if (m < s[i]) m = s[i];
            }
            std::cout << m << std::endl;
        }
    }
    return 0;
}

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