First Application

Here is a simple contract with a count that has a default value of 0.

You can increment, decrement, and get the count.

cadence

access(all) contract Counter {
   access(all) var count: Int

   access(all) fun increment() {
      self.count = self.count + 1
   }

   access(all) fun decrement() {
      self.count = self.count - 1
   }

   // technically this function isn't
   // needed, because we can read
   // the `count` variable directly
   access(all) fun get(): Int {
      return self.count
   }

   init() {
      self.count = 0
   }
}