code 34244;
    procedure GSSINVERB(A, N, AUX); value N; integer N;
    array A, AUX;
    begin integer array RI, CI[1:N];
        GSSELM(A, N, AUX, RI, CI);
        if AUX[3] = N then 
        ERBELM(N, AUX, INV1(A, N, RI, CI, true ))
    end GSSINVERB;
        eop