      TEST (N=4)
C COMPUTE S = (T INVERSE), WHERE T IS A NONSINGULAR, UPPER
C TRIANGULAR MATRIX.
      DIMENSION (S(N,N), T(N,N))
C
C INPUT T.
      FOR J = 1 TO N BY 1
          FOR I = J TO 1 BY -1
              INPUT (T(I,J))
              END (I)
          END (J)
C
C COMPUTE S.
      FOR K = 1 TO N BY 1
          S(K,K) = 1.0/T(K,K)
          FOR I = K-1 TO 1 BY -1
              S(I,K) = -SUMMATION(T(I,J)*S(J,K), J = I+1 TO K)/T(I,I)
              END (I)
          END (K)
C
C OUTPUT S.
      FOR J = 1 TO N BY 1
          FOR I = J TO 1 BY -1
              OUTPUT (S(I,J))
              END (I)
          END (J)
      *STOP
