Example 3.5

FORTRAN Version

!
      PROGRAM P36
!
!     Nested IF blocks
!
      IMPLICIT NONE
      LOGICAL :: SINGLE
      CHARACTER (LEN=20) :: NAME
      INTEGER :: I,J,AGE,N,TAGE
      REAL :: AVE
!
!
      PRINT *, 'This is Program >> P36  - Nested IF blocks'
!
!     READ DATA
!
      READ *,I
!
      N=0
      TAGE=0.0
L1:      DO J=1,I
          READ * ,NAME,SINGLE,AGE
          PRINT * ,NAME,SINGLE,AGE
          IF(SINGLE)THEN
             N=N+1
             TAGE=TAGE+AGE
             IF(N  ==  5)THEN
                AVE=TAGE/5.0
                PRINT * ,'AVERAGE AGE OF ', &
                'FIRST FIVE SINGLES IS'
                PRINT * ,AVE
                STOP
             END IF
          END IF
      END DO L1
      STOP
      END PROGRAM P36

7
'Bruce Perras'         T  17.0
'Donna Smith'          F  23.0
'Suzie Gascon'         T  19.0
'Mary Brown'           T  22.0
'Jane Jones'           T  35.0
'Sophie Rochon'        F  29.0
'Alex Reid'            T  25.0

              +--------------------------------------------------+
              |     32-bit Power for Lahey Computer Systems      |
              |   Phar Lap's 386|DOS-Extender(tm) Version 7.0    |
              |  Copyright (C) 1986-94 Phar Lap Software, Inc.   |
              |           Available Memory = 14880 Kb            |
              +--------------------------------------------------+


This is Program >> P36  - Nested IF blocks
Bruce Perras         T          17
Donna Smith          F          23
Suzie Gascon         T          19
Mary Brown           T          22
Jane Jones           T          35
Sophie Rochon        F          29
Alex Reid            T          25
AVERAGE AGE OF FIRST FIVE SINGLES IS
    23.6000    

Pascal Version

PROGRAM p36 (input, output);
VAR
  single : BOOLEAN;
  single_tmp, n : INTEGER;
  name : STRING[20];
  tage, age, ave : REAL;
BEGIN
  n := 0;
  tage := 0.0;
  readln ( name, single_tmp, age );
  WHILE ( n < 5 ) DO
    BEGIN
      IF ( single_tmp = 1 ) THEN single := true;
      IF ( single_tmp = 0 ) THEN single := false;
      IF single THEN
        BEGIN
          n := n + 1;
          tage := tage + age;
          IF ( n = 5 ) THEN
            BEGIN
              ave := tage/5.0;
              writeln ( 'average age of first five singles is ' );
              writeln ( ave )
            END { end if }
        END; { end if }
      readln ( name, single_tmp, age )
    END { end while }
END.

Bruce Perras         1  17.0
Donna Smith          0  23.0
Suzie Gascon         1  19.0
Mary Brown           1  22.0
Jane Jones           1  35.0
Sophie Rochon        0  29.0
Alex Reid            1  25.0

Last modified: 08/07/97