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java extended class inheritance [closed]

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Sum s = new Sum();
Sum.SetToZero z = new Sum.SetToZero();
Scanner input = new Scanner(System.in);
String read = input.nextLine();
while (!read.equals("end")) {
if (read.equals("add")) {
s.add()
}
else if (read.equals("get")) {
System.out.println(s.returnTotal());
}
else if (read.equals("zero")) {
z.zero();
}
read = input.nextLine();
}
class:
public class Sum {
int total = 0;
public void add() {
total += 1;
}
public int returnTotal() {
return total;
}
public static class SetToZero extends Sum {
public void zero() {
total = 0;
}
}
}
input:
add
add
zero
add
get
add
get
end
output:
3
4
output wanted:
1
2
Shouldn't the subclass inherit the total and set it to zero? What am I doing wrong? I know I could just move the zero into the main class but I want it to be in a separate class. thx for your help.

By making your total variable static, you can get the desired output.
class Sum {
static int total = 0;
public void add() {
total += 1;
}
public int returnTotal() {
return total;
}
public static class SetToZero extends Sum {
public void zero() {
total = 0;
}
}
}

Apart from things pointed out in names like not using lowecase letters to start your class name; I think the reason why it's not working is because you're using two different variable instances for Sum and Sum.SetToZero. You don't need to create a new variables since SetToZero has all the attributes of Sum. I think you should change this:
Sum s = new Sum();
Sum.SetToZero z = new Sum.SetToZero();
Sum.SetToZero s = new Sum.SetToZero(); // use s for all operations
Here is how your modified main method would look:
public static void main(String[] args) {
Sum.SetToZero s = new Sum.SetToZero();
Scanner input = new Scanner(System.in);
String read = input.nextLine();
while (!read.equals("end")) {
if (read.equals("add")) {
s.add();
}
else if (read.equals("get")) {
System.out.println(s.get());
}
else if (read.equals("zero")) {
s.zero();
}
read = input.nextLine();
}
}
When I ran this, I saw expected output:
src : $ java Sum
add
add
zero
add
get
1
add
get
2
end

Create an array checking previous items in another array [closed]

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I'm trying to create an array of numbers, starting from a big number, which is a string, and then splited to create an array.
This array has numbers from 1 to 6.
I want to create a new array of 29 items, checking the last 3 items. For instance, if the current item to add is number 4, it will check for item 3, 2, and 1. I want it to check if any of the other 3 items are the same as the current, and if is the same, it will skip to next number.
The idea, is not to have repeated numbers in a "range" of 4 items.
I also want to do another thing, and is that if the current item is number 1, it would check the last 6 items, instead of just the last 3. Only when the item is number 1. I just haven't found a way to do it.
I hope someone could help me.
Here's the current code:
import java.io.*;
import java.util.*;
public class Randomizer {
public static String numbers = "1632544362511653244213652164535316243164251654235231465312645164233462153465124361522316545326412354165412633214654531626513246124351423565431623162453625412564325134634562136145256142342365161423542563151426325146335241613645225431656324164351215263453642123416561345264215321536436451243156263542125631415624314536235124662145152436352164436512645312264315432651216345624315421563516423465213614352621543342516352614";
public static void main(String[] args) {
show("\n");
String[] nums = numbers.split("(?!^)"), finalNums = new String[29];
for (int i = 0; i < finalNums.length; i++) {
finalNums[i] = newnumber(nums, i);
}
for (String num : finalNums) {
show(num + "-");
}
}
public static String newnumber(String[] array, int start) {
String num = "x";
String act = array[start];
for (int i = start; i < array.length; i++) {
int a = start - 1, b = start - 2, c = start - 3, d = start - 4;
if (a >= 0 && b >= 0 && c >= 0 && d >= 0) {
String na = array[a], nb = array[b], nc = array[c], nd = array[d];
if (act != na && act != nb && act != nc && act != nd) {
num = act;
} else {
}
} else {
num = act;
}
}
return num;
}
public static void show(String s) {
System.out.print(s);
}
public static void show(int s) {
System.out.print(s);
}
public static void show(float s) {
System.out.print(s);
}
public static void show(double s) {
System.out.print(s);
}
}
The output is:
1-6-3-2-5-4-4-3-6-2-5-1-1-6-5-3-2-4-4-2-1-3-6-5-2-1-6-4-5
What I expect to get is something like:
1-6-3-2-5-4-6-1-2-5-3-4-6-5-1-2-5-4-6-3-2-1-2-4-5-6-3-2-1

How do I convert decimal 75.95 to 7595 in Java?

I have a program in which i need to convert double 75.95 to normal integer 7595. How do I write the actual program?
My code is:
class test5 {
public static void main(String args[]) {
double d = 75.95;
System.out.println("Price before converting = "+d);
int i = (int)d;
System.out.println("(float)d = "+i);
}
}

Any particular reason why multiplying by 100 wouldn't work?
class test5 {
public static void main(String args[]) {
double d = 75.95;
System.out.println("Price before converting = "+d);
long i = Math.round(d * 100);
System.out.println("(float)d = "+i);
}
}
You have to be careful with rounding errors. See: Losing precision converting from int to double in java

Now my code is this and its working :) thanks all of you :)
class test5
{
public static void main(String args[])
{
double d = 75.95;
{
System.out.println("Price before converting = "+d);
int i = (int)(d*100);
System.out.println("Answer after converting = "+i);
}
}
}

You can multiply by a constant 100 (if there are only, and always two decimal points). If there are more, you could use String.valueOf(double) and remove the '.' and call a double a double (not a float). Something like
double d = 75.95;
// int val = (int) (d * 100); // <-- or this.
String str = String.valueOf(d).replace(".", "");
int val = Integer.valueOf(str);
System.out.printf("(double)%f = (int)%d%n", d, val);
Which outputs
(double)75.950000 = (int)7595

How to convert big int number to Binary ? - Java

I am trying to convert int to binary and i am doing below code.
public static String intToBinary16Bit(String strInt) {
String bin = Integer.toBinaryString(strInt);
return String.format("%016d", Integer.parseInt(bin));
}
So, if i am giving strInt = 0211 than it is working fine and giving the output
0000001000010001.
But, if i am giving strInt = 4527 than it is throwing NumberFormateException.
How can I resolved this issue ?

Try what eznme suggests here:
public class A {
public static void main(String[] args) {
int a = Integer.parseInt(args[0]);
System.out.println(a);
int bit=1;
for(int i=0; i<32; i++) {
System.out.print(" "+(((a&bit)==0)?0:1));
bit*=2;
}
}
}

Try the following method, it uses recursion for conversion.
private static void toBinary(int number) {
int remainder;
if (number <= 1) {
System.out.print(number);
return;
}
remainder = number % 2;
toBinary(number >> 1);
System.out.println(remainder);
}

You try:
Long.toBinaryString(2199023255552L);
Java long to binary

Smallest and Largest integers using if/else only [closed]

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Edit the question to include desired behavior, a specific problem or error, and the shortest code necessary to reproduce the problem. This will help others answer the question.
Closed 8 years ago.
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Here is my code to display smallest and largest integer by taking 5 inputs from user...it works for smallest values but not for largest and I cant figure out the problem...please help
import java.util.Scanner;
public class LargestAndSmallestIntegers {
public static void main(String[] args) {
Scanner input=new Scanner(System.in);
int a,b,c,d,e;
int small,large;
System.out.println("Enter five integer values...");
a=input.nextInt();
small=a;
large=a;
b=input.nextInt();
if (small<b)
{
large=b;
}
else
{
small=b;
}
c=input.nextInt();
if (small<c)
{
large=c;
}
else
{
small=c;
}
d=input.nextInt();
if (small<d)
{
large=d;
}
else
{
small=d;
}
e=input.nextInt();
if (small<e)
{
large=e;
}
else
{
small=e;
}
input.close();
System.out.printf("%d is smallest and %d is largest", small,large);
}
}

private int a = input.nextInt(),
b = input.nextInt(),
c = input.nextInt(),
d = input.nextInt(),
e = input.nextInt();
private int small, large;
small = min(a,b);
small = min(small,c);
small = min(small,d);
small = min(small,e);
large = max(a,b);
large = max(large,c);
large = max(large,d);
large = max(large,e);
private int min(int a, int b) {
if (a < b) return a else return b;
}
private int max(int a, int b) {
if (a > b) return a else return b;
}
I think this works ;)

it works for smallest values but not for largest
As lared pointed out, comparing against small to determine large is flawed. You must include something like this in your comparison logic:
if (large < b)
{
large = b;
}
in addition to your existing comparison:
if (small > b)
{
small = b;
}

you always just check for the smallest value. you also need to check
if (small<e)
{
if(large < e)
{
large=e;
}
}