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#include <iostream>
#include <vector>
using namespace std;

int main() {
    vector<int> digits;
    int start_from = 3;
    int d = start_from;
    int carry = 0;


    while (true) {
        digits.push_back(d);
        int a = d * 3 + carry;
        d = a % 10;
        carry = a / 10;

        if (carry == 0 && d == start_from)
            break;
    }

    for (int i = digits.size() - 1; i >= 0; i--)
        cout << digits[i];

    cout << endl;
    return 0;
}