PROGRAM SUB_INT_COUNT

IMPLICIT NONE

INTEGER :: u, v, MyProd, MySum

CHARACTER :: Flag

DO

PRINT *, "Enter two positive integers u and v:"

READ *, u, v

CALL IntCount(u*v,MyProd)

PRINT *, "The number of digits in the product is: ", MyProd, "."

CALL IntCount(u+v,MySum)

PRINT *, "The number of digits in the sum is: ", MySum, "."

PRINT *, 'Continue? If not, press "n" or "N"; else press any other key.'

READ *, Flag

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

END DO

CONTAINS

SUBROUTINE IntCount(n,IC)

INTEGER :: k

INTEGER, INTENT(IN) :: n

INTEGER, INTENT(OUT) :: IC

k=n

IC=0

DO

k=k/10

IC=IC+1

IF (k==0) EXIT

END DO

END SUBROUTINE IntCount

END PROGRAM SUB_INT_COUNT