\(
\newcommand{\Ds}{\displaystyle}
\newcommand{\PP}{{\mathbb P}}
\newcommand{\RR}{{\mathbb R}}
\newcommand{\KK}{{\mathbb K}}
\newcommand{\CC}{{\mathbb C}}
\newcommand{\ZZ}{{\mathbb Z}}
\newcommand{\NN}{{\mathbb N}}
\newcommand{\TT}{{\mathbb T}}
\newcommand{\QQ}{{\mathbb Q}}
\newcommand{\Abs}[1]{{\left|{#1}\right|}}
\newcommand{\Floor}[1]{{\left\lfloor{#1}\right\rfloor}}
\newcommand{\Ceil}[1]{{\left\lceil{#1}\right\rceil}}
\newcommand{\sgn}{{\rm sgn\,}}
\newcommand{\Set}[1]{{\left\{{#1}\right\}}}
\newcommand{\Norm}[1]{{\left\|{#1}\right\|}}
\)