If \( \vec{a}=\hat{i}+\hat{j}+\hat{k} \), \( \vec{b}=\hat{j}-\hat{k} \) and \( \vec{c} \) be three vectors such that \( \vec{a}\times\vec{c}=\vec{b} \) and \( \vec{a}\cdot\vec{c}=3 \), then \( \vec{c}\cdot(\vec{a}-2\vec{b}) \) is equal to ______.
