Java - Compiler errors

// This program illustrates the use of Java datatypes.

import java.io.*;

import java.lang.*;

public class Code3

{ //begins Nums

public static void main(String args[])

{

int x= 5;

int y= 2;

int z = 0;

long a, b = 0;

double d= 5.12345;

byte c = 0;

//float e = 34.2; compiler error: (1)

float e = 34.2F; //or float e = (float) 34.2;

short f,g,h;

f =2; g = f;

//h = f * g; complier error (2)

//c = a; compiler error (3)

//z = 5L; compiler error (4)

a = 6; //promotion of int to long

b = 1000L;

z = (int) (5000L + b); // (5)

c = (byte) (x*y); // (6)

a = c;

System.out.println(c);

System.out.println(c * a);

System.out.println(b);

z = (int) d; // lose decimal places

System.out.println(z);

} //end main

} //end Nums