Let A′{\displaystyle A'} be a successful attacker on a digital signature system that creates n{\displaystyle n} bit signatures. This image shows how an attacker A{\displaystyle A}, who attacks n+1{\displaystyle n+1} bit digital signature systems,  can be reduced to A′{\displaystyle A'}. The challenger C{\displaystyle C} and the attacker A′{\displaystyle A'} work exactly as described in File:Digital signature attacker.svg.
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