code 34391;
    procedure CHLSOL1(A, N, B); value N; integer N; array A, B;
    begin integer I, II;

        II:= 0;
        for I:= 1 step 1 until N do 
        begin II:= II + I;
            B[I]:= (B[I] - VECVEC(1, I - 1, II - I, B, A)) / A[II]
        end;
        for I:= N step - 1 until 1 do 
        begin B[I]:= (B[I] -
                SEQVEC(I + 1, N, II + I, 0, A, B)) / A[II];
            II:= II - I
        end 
    end CHLSOL1;
        eop