An undercover sting operation to root out cabbies who overcharge passengers failed to net a single swindler, the city announced yesterday.

It’s a stark turnabout from last year, when a widespread investigation found that 45 percent of hacks had overcharged customers at least once by using the double-rate suburban fare.

Fifty-nine cabbies were charged with ripping people off.

“We believe the GPS units in taxis, public awareness about appropriate rates, and the deterrent effect of last year’s arrests have had a positive impact for tourists and residents,” said Department of Investigation Commissioner Rose Gill Hearn.