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For $\triangle ABC$, all of its side lengths are integers. The primeter of $\triangle ABC$ with a side of length $12$ and a side length of $7$ is at least ． 
Overseas Competition->Knowledge Point->Calculation Modules->Basic Concepts of Equation->Inequalities
We know from the triangle inequality that the last side, $s$, fulfills $s+7\textgreater12$. $P=s+7+12\textgreater12+12$. Therefore, $P\textgreater24+1=25$ 