Does the ac use electric or gas more cause some people have told me it uses more gas while other say it uses more electric

An automotive AC compressor works under the same principle weather it is a gas engine or diesel engine. Using the output from the engine via the crank pulley, will use a belt to turn the pulley on the AC compressor. Although there are countless applications, they all generally work the same. In my opinion, as far as the electric used is really irreverent seeing as how the engine in a vehicle is essentially it's own generator. In the end, you're paying for fuel to power it which would be the concern.

Having the AC on uses more gas- the electrical usage makes no difference because you have an alternator charging the system, making more juice all the time- whether diesel or gas, the principle is the same