! Try yukicoder
! author: Leonardone @ NEETSDKASU
 
      PROGRAM yukicoder
          INTEGER :: a(7), i, j, k, d(7), f(7), r, b(7), x(7)
          
          READ (*,*) a
          
          DO j = 0, 6
              x(j + 1) = 10 ** j
          END DO
          
          r = 1
          DO i = 123456, 6543210
              IF (r > 0) THEN
                  DO j = 1, 7
                      f(j) = 0
                  END DO
                  r = 0
              END IF
              DO j = 1, 7
                  k = MOD(i / x(j), 10) + 1
                  IF (k > 7) exit
                  IF (f(k) > 0) exit
                  f(k) = 1
                  b(j) = a(k)
                  r = r + 1
              END DO
              IF (r < 7) cycle
              IF (b(1) >= b(3)) cycle
              IF (b(2) >= b(4)) cycle
              IF (b(3) >= b(5)) cycle
              IF (b(4) >= b(6)) cycle
              IF (b(5) >= b(7)) cycle
              IF (b(1) <= b(2) .and. b(2) <= b(3)) cycle
              IF (b(2) <= b(3) .and. b(3) <= b(4)) cycle
              IF (b(3) <= b(4) .and. b(4) <= b(5)) cycle
              IF (b(4) <= b(5) .and. b(5) <= b(6)) cycle
              IF (b(5) <= b(6) .and. b(6) <= b(7)) cycle
              
              PRINT '(A)', 'YES'
              STOP
              
          END DO
          
          PRINT '(A)', 'NO'
          
      END PROGRAM yukicoder