Does a Class component in React need to have a constructor like the following example:

class App extends React.Component {
    constructor() {
        super()
        this.state = {
            count: 0
        }
    }
render() {
  ...
}
}

Or now we can define a Class component without using a constructor, like the following example?:

class App extends React.Component {
        this.state = {
            count: 0
        }
render() {
  ...
}
}

Which one is correct?
Do we still need to write the constructor for a Class component?