Java thread synchronization

Main.java

class ZapOne {
    synchronized void print(int n) {
        for (int i = 1; i <= 5; i++) {
            System.out.println(n * i);
        }
    }
} 

//Synchronized Function
class coding extends Thread {
    ZapOne z;
    
    coding(ZapOne z) {
        this.z = z;
    } 
    
    // First Thread
    public void run() {
        z.print(2);
    }
}

class zap extends Thread {
    ZapOne z;
    
    zap(ZapOne z) {
        this.z = z;
    } 
    
    // Second Thread
    public void run() {
        z.print(10);
    }
}

public class Main {
    public static void main(String[] args) {
        
        ZapOne obj = new ZapOne(); // Synchronised Object
        coding z1 = new coding(obj);
        
        zap z2 = new zap(obj); // Thread Object
        
        z1.start();
        z2.start(); // Start Function 
    }
}