PROGRAM bubblesort
       IMPLICIT NONE
       REAL x(10),aux
       INTEGER i,n,ok
       WRITE(*,*)'Enter the length of the string please'
       READ(*,*)n
       WRITE(*,*)'Enter the ',n,' elements please'
       DO i=1,n
          READ(*,*)x(i)
       ENDDO
    99 ok=0
       DO i=1,n-1
          IF(x(i)>x(i+1)) THEN
             aux=x(i)
             x(i)=x(i+1)
             x(i+1)=aux
             ok=1
           ENDIF
        ENDDO
        IF(ok/=0) GOTO 99
        DO i=1,n
           WRITE(*,*)x(i)
        ENDDO
        END PROGRAM bubblesort