NET INCOME PER SHARE (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Apr. 30, 2019	Apr. 30, 2018	Apr. 30, 2019	Apr. 30, 2018
Numerator:
Net income (loss)	$ 182	$ 205	$ 686	$ (115)
Denominators:
Basic weighted-average shares (in shares)	317,000,000	322,000,000	318,000,000	323,000,000
Potential common shares - stock options and other employee stock plans (in shares)	4,000,000	4,000,000	4,000,000	0
Diluted weighted average shares (in shares)	321,000,000	326,000,000	322,000,000	323,000,000
Antidilutive securities excluded from computation of Earnings Per Share, amount (in shares)	0	96,800	0	6,600,000

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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