What is the only ordered quadruple of integers $$\((a, b, c, d)\)$$ for which $$\(a+2 b+3 c+4 d=30\)$$ and $$\(a^{2}+b^{2}+c^{2}+d^{2}=30\)$$ ? Note: Please enter the sum of $$\(a, b, c\)$$, and $$\(d\)$$ as your answer, that is entering the value of $$\(a+b+c+d\)$$.

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