#include <iostream>

int main()
{
    class Bar {
    public:
        int lastResult;
        int frac(int n) {
            if (n == 0) return 1;
            return (lastResult = n * frac(n - 1));
        }
    };

    Bar x;
    x.frac(10);
    std::cout << x.lastResult << std::endl;
}

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