He was also ordered to carry out 55 rehabilitation days, 43 accredited sex offender program days and 60 hours of unpaid work.
Police said Dias exposed himself to a woman on Moor Road in Wath upon Dearne and performed a lewd act in front of two teenage girls in the same area the following day.
A week later, Dias exposed himself to a woman on the Trans Pennine Trail in the Dearne Valley and sexually assaulted her.
Police investigations later revealed that Dias had followed his victims for extended periods of time, on foot or in his car, and waited until they were alone or isolated.
Det Sergeant David Baker and DC Dawn Murray said: “Dias exhibited dangerous, predatory behaviour.
“We would like to commend the women and girls in this case for their bravery in reporting these horrific crimes to us.”
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