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x A x B - ,
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(mh A r h A r ' g r g r ') = (m h A r + r ' g r + r').
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(mh A r + r ' h B s g r + r' g s).
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m
m e A mod n,
m e A e B mod n,
,
m e B mod n,
B, m. , ,
, c = m e A mod n c '= m e B mod n r, s ,
r e A + s e B= 1
m = c r (c ') s mod n.
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