PROGRAM FUNCTIONSUM7

IMPLICIT NONE

INTEGER :: K

CHARACTER :: Flag

DO

PRINT *, "Enter a positive integer K, which is greater &

&than or equal to 10."

READ *, K

PRINT *, "The required sum is: ", Sum7(K)

PRINT *, "Continue? If not, press ""n"" or ""N""; else &

&press any other key."

READ *, Flag

IF ((Flag=="n") .OR. (Flag=="N")) THEN

EXIT

END IF

END DO

CONTAINS

FUNCTION Sum7(n)

INTEGER :: Sum7, i

INTEGER, INTENT(IN) :: n

Sum7=0

DO i=1, n

IF (MOD(i,7)==0) THEN

Sum7=Sum7+i

END IF

END DO

END FUNCTION Sum7

END PROGRAM FUNCTIONSUM7