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C******************************************************************************
C FILE: omp_workshare1.f
C DESCRIPTION:
C OpenMP Example - Loop Work-sharing - Fortran Version
C In this example, the iterations of a loop are scheduled dynamically
C across the team of threads. A thread will perform CHUNK iterations
C at a time before being scheduled for the next CHUNK of work.
C AUTHOR: Blaise Barney 5/99
C LAST REVISED: 01/09/04
C******************************************************************************
PROGRAM WORKSHARE1
INTEGER NTHREADS, TID, OMP_GET_NUM_THREADS,
+ OMP_GET_THREAD_NUM, N, CHUNKSIZE, CHUNK, I
PARAMETER (N=100)
PARAMETER (CHUNKSIZE=10)
REAL A(N), B(N), C(N)
! Some initializations
DO I = 1, N
A(I) = I * 1.0
B(I) = A(I)
ENDDO
CHUNK = CHUNKSIZE
!$OMP PARALLEL SHARED(A,B,C,NTHREADS,CHUNK) PRIVATE(I,TID)
TID = OMP_GET_THREAD_NUM()
IF (TID .EQ. 0) THEN
NTHREADS = OMP_GET_NUM_THREADS()
PRINT *, 'Number of threads =', NTHREADS
END IF
PRINT *, 'Thread',TID,' starting...'
!$OMP DO SCHEDULE(DYNAMIC,CHUNK)
DO I = 1, N
C(I) = A(I) + B(I)
WRITE(*,100) TID,I,C(I)
100 FORMAT(' Thread',I2,': C(',I3,')=',F8.2)
ENDDO
!$OMP END DO NOWAIT
PRINT *, 'Thread',TID,' done.'
!$OMP END PARALLEL
END
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