Macro iterate

macro_rules! iterate {
    ($x:ident, $y:ident, $z:ident => $body:block) => { ... };
}

A macro to iterate over the state array.

This macro is used to iterate over the state array in the Keccak permutation. It allows for more concise code when performing operations on the state array. The macro takes three identifiers $x, $y, and $z which represent the indices of the state array. The body of the macro is executed for each iteration.