C********************************************************************* 
 
      SUBROUTINE LUERRM(MERR,CHMESS) 
 
C...Purpose: to inform user of errors in program execution. 
      COMMON/LUJETS/N,K(4000,5),P(4000,5),V(4000,5) 
      COMMON/LUDAT1/MSTU(200),PARU(200),MSTJ(200),PARJ(200) 
      SAVE /LUJETS/,/LUDAT1/ 
      CHARACTER CHMESS*(*) 
 
C...Write first few warnings, then be silent. 
      IF(MERR.LE.10) THEN 
        MSTU(27)=MSTU(27)+1 
        MSTU(28)=MERR 
        IF(MSTU(25).EQ.1.AND.MSTU(27).LE.MSTU(26)) WRITE(MSTU(11),5000) 
     &  MERR,MSTU(31),CHMESS 
 
C...Write first few errors, then be silent or stop program. 
      ELSEIF(MERR.LE.20) THEN 
        MSTU(23)=MSTU(23)+1 
        MSTU(24)=MERR-10 
        IF(MSTU(21).GE.1.AND.MSTU(23).LE.MSTU(22)) WRITE(MSTU(11),5100) 
     &  MERR-10,MSTU(31),CHMESS 
        IF(MSTU(21).GE.2.AND.MSTU(23).GT.MSTU(22)) THEN 
          WRITE(MSTU(11),5100) MERR-10,MSTU(31),CHMESS 
          WRITE(MSTU(11),5200) 
          IF(MERR.NE.17) CALL LULIST(2) 
          STOP 
        ENDIF 
 
C...Stop program in case of irreparable error. 
      ELSE 
        WRITE(MSTU(11),5300) MERR-20,MSTU(31),CHMESS 
        STOP 
      ENDIF 
 
C...Formats for output. 
 5000 FORMAT(/5X,'Advisory warning type',I2,' given after',I6, 
     &' LUEXEC calls:'/5X,A) 
 5100 FORMAT(/5X,'Error type',I2,' has occured after',I6, 
     &' LUEXEC calls:'/5X,A) 
 5200 FORMAT(5X,'Execution will be stopped after listing of last ', 
     &'event!') 
 5300 FORMAT(/5X,'Fatal error type',I2,' has occured after',I6, 
     &' LUEXEC calls:'/5X,A/5X,'Execution will now be stopped!') 
 
      RETURN 
      END