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java - using a variable in constructor in a method outside of constructor

if i have a constructor like so:

    public Constructor (int a, int b){

        int c =  a;
        int d =  b; 
    }

How can i then use variable c and d in a method within the same class as the constructor because trying to use just the variables name in the method doesn't seem to work?

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In fact your code will not compile - int c = int a is not valid.

I assume that you meant: - int c = a;.

How can i then use variable c and d in a method within the same class as the constructor

You can't because you have declared them as local variables whose scope ends when the constructor ends execution.

You should declare them as instance variables.

public class MyClass {
    int c;
    int d;

    public MyClass(int a, int b){

        this.c = a;
        this.d = b; 
    }

    public void print() {
        System.out.println(c + " : " + d);
    }
}

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