NET INCOME PER SHARE (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended
Jan. 31, 2020	Jan. 31, 2019
Numerator:
Net income	$ 197	$ 504
Denominators:
Basic weighted-average shares (in shares)	310	318
Potential common shares - stock options and other employee stock plans (in shares)	3	4
Diluted weighted average shares (in shares)	313	322

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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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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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