\(\left(\left|12\right|-12^0\right).1^{12}-\left|-12\right|\)
\(=\left(12-1\right).1^{12}-\left|-12\right|\)
\(=11.1^{12}-\left|-12\right|\)
\(=11.1-\left|-12\right|\)
\(=11-\left|-12\right|\)
\(=11-12\)
\(=-12+11\)
\(=-\left(12-11\right)\)
\(=-1\)