It took the better part of a year, but Manhattan DA Cy Vance has kept his promise to treat last April’s Times Square wilding cases “with the attention and seriousness they deserve.”

As a result, 21-year-old Rayvon Guice, who admitted aiming to kill when he fired a .380-caliber handgun into a crowd, wounding two, will spend the next 16 years in prison for attempted murder.

Guice agreed to cop a plea to serious counts and accept the time, rather than risk a possible 25-year term if convicted at trial. (He’s also facing drug charges in an unrelated case.)

Which means at least one of those behind the wilding — which left four people shot and three cops hurt — will do some hard time.

Last summer, recall, Vance’s office let another accused felon in the case walkwith no more than a year of counseling and eight days of community service because he had no prior record, having committed a mere “act of stupidity.”

Never mind that the rampage — which, it turns out, has been an annual “event” for years now — terrorized thousands.

It seems Vance got the message of the uproar over that outcome.

The DA took office promising to address the “root causes” of crime, a task better left to sociologists than to prosecutors.

But while the root cause of crime is debatable, a key reason for continued crime is not — if criminals believe that they can get away with it, they’ll try to.

Happily, Vance has just sent a strong message to the contrary.