[cyber]

єм?)

function action ( index, val ) {

        let matrixClone = Matrix.clone();
        let vectorClone = vector.clone();
        vectorClone[index] += val;
        matrixClone.swapCells(vector, vectorClone);
        children.push(new Node({matrix: matrixClone}));
}

 if (vector[0] !== 0) {
   action ( 0, -1 );
 }