For compatibility with FTN77, FTN95 offers an alternative WHILE statement. Its
general form is
WHILE (logical expression) DO
. . . .
The WHILE-block may contain any executable Fortran statements. WHILE-blocks may
be nested within each other or within IF-, ELSE-, and ELSEIF-blocks and/or DO
statements. The rules of nesting are the same as those for the IF construct.
An ENDWHILE statement can be labelled but may only be referenced from within the
J = 0
I = LIST(I)
J = J+1