This problem is know as Clock angle problem where we need to find angle between hands of an analog clock at

Example:

Input:  h = 12:00, m = 30.00
Output: 165 degree

The idea is to take 12:00 (h = 12, m = 0) as a reference. Following are detailed steps.



1) Calculate the angle made by hour hand with respect to 12:00 in h hours and m minutes.
2) Calculate the angle made by minute hand with respect to 12:00 in h hours and m minutes.

3) The difference between two angles is the angle between two hands.





How to calculate the two angles with respect to 12:00? 


The minute hand moves 360 degree in 60 minute(or 6 degree in one minute) and hour hand moves 360 degree in 12 hours(or 0.5 degree in 1 minute). In h hours and m minutes, the minute hand would move (h*60 + m)*6 and hour hand would move (h*60 + m)*0.5.





so the final answer will be the difference of the above formula...



(h*60+m)*0.5 - (h*60+m)*6




program






public class angle
{
    public static void main(String[] args)
    {
        System.out.println(cal_angle(10,34));
    }
    
    public static int cal_angle(int hour,int min)
    {
        int h_angle=(int)((hour*60+min)*0.5);
        int angle=(min*6)-h_angle;
        //now calculate minimum angle...
       
if (angle<0) angle=-angle;
  return Math.min(360-angle,angle);
         
    }
}

output
113

• algorithm

//notepad import java.awt.*; import javax.swing.*; import java.awt.event.*; import java.util.Scanner; import java.io.*; public class Notepad extends JFrame implements ActionListener { private TextArea textarea = new TextArea("",0,0,TextArea.SCROLLBARS_VERTICAL_ONLY); private MenuBar menubar = new MenuBar(); private Menu file = new Menu(); private MenuItem openfile = new MenuItem(); private MenuItem savefile = new MenuItem(); private MenuItem close = new MenuItem(); public Notepad(){ this.setSize(500,500); this.setTitle("Java...Notepad Tutorial"); setDefaultCloseOperation(EXIT_ON_CLOSE); this.textarea.setFont(new Font("Century Gothic",Font.BOLD,12)); this.getContentPane().setLayout(new BorderLayout()); this.getContentPane().add(textarea); this.setMenuBar(this.menubar); this.menubar.add(this.file); this.file.setLabel("File"); this.openfile.setLabel("open"); this.openfile.addActionListener(this); this.file.add(this.openfile); this.savefile.setLabel("Save"); this.savefile.addActionListener(this); this.file.add(this.savefile); this.close.setLabel("Close"); this.close.addActionListener(this); this.file.add(close); } public void actionPerformed(ActionEvent e) { if(e.getSource()==close) { this.dispose(); } if(e.getSource()==openfile) { JFileChooser open = new JFileChooser(); int option = open.showOpenDialog(this); if(option == JFileChooser.APPROVE_OPTION) { this.textarea.setText(""); try{ Scanner scan = new Scanner(new FileReader(open.getSelectedFile().getPath())); while(scan.hasNext()) this.textarea.append(scan.nextLine() +'\n'); } catch(Exception ex) { System.out.println(ex.getMessage()); } } } if(e.getSource()==savefile) { JFileChooser save = new JFileChooser(); int option = save.showSaveDialog(this); if(option == JFileChooser.APPROVE_OPTION) { try{ BufferedWriter out = new BufferedWriter(new FileWriter(save.getSelectedFile().getPath())); out.write(this.textarea.getText()); out.close(); } catch(Exception ex) { System.out.println(ex.getMessage()); } } } } public static void main(String args[]) { Notepad app = new Notepad(); app.setVisible(true); } }

Output

• fileinputstream
• FileOutputStream
• frame

//tic tac toe..using applet ... import java.applet.Applet; import java.awt.*; import java.awt.event.*; /** // // @author - techieRJ // **/ //<applet code=tic_tac_toe width=500 height=500></applet> public class tic_tac_toe extends Applet implements ActionListener { Button FF,FS,FT,SF,SS,ST,TF,TS,TT; String F_F="z",F_S="z",F_T="z",S_F="z",S_S="z",S_T="z",T_F="z",T_S="z",T_T="z"; Button Select_X,Select_O,Replay; //where f=first s=second t=third...first letter is for row and second is for column; Panel panel1,panel2,panel3,cardpanel; Label lbl_win; CardLayout card; String value_selected; String last_value="O"; public void init() { Font font=new Font("Verdana", Font.BOLD, 20); setFont(font); setForeground(Color.blue); setBackground(Color.yellow); card = new CardLayout(); setLayout(card); cardpanel = new Panel(); add(cardpanel); cardpanel.setLayout(card); //first panel panel1 = new Panel(); cardpanel.add(panel1,"First"); Select_X = new Button("Select X"); Select_O = new Button("Select O"); panel1.add(Select_X); panel1.add(Select_O); //add action event Select_X.addActionListener(this); Select_O.addActionListener(this); //end of panel 1 //panel 2 panel2 =new Panel(); cardpanel.add(panel2,"Second"); panel2.setLayout(new GridLayout(3,3)); FF = new Button(""); FS = new Button(""); FT = new Button(""); SF = new Button(""); SS = new Button(""); ST = new Button(""); TF = new Button(""); TS = new Button(""); TT = new Button(""); panel2.add(FF); panel2.add(FS); panel2.add(FT); panel2.add(SF); panel2.add(SS); panel2.add(ST); panel2.add(TF); panel2.add(TS); panel2.add(TT); FF.addActionListener(this); FS.addActionListener(this); FT.addActionListener(this); SF.addActionListener(this); SS.addActionListener(this); ST.addActionListener(this); TF.addActionListener(this); TS.addActionListener(this); TT.addActionListener(this); //end of panel2 //start of panel 3 panel3 = new Panel(); panel3.setLayout(new GridLayout(2,1)); cardpanel.add(panel3,"Third"); Replay = new Button("Repaly"); lbl_win = new Label(""); panel3.add(lbl_win); panel3.add(Replay); lbl_win.setBounds(10,10,100,200); Replay.setBounds(50,50,300,200); Replay.addActionListener(this); //end of panel 3 } public void actionPerformed(ActionEvent e) { //action first event if(e.getSource()==Select_X) { value_selected= "X"; last_value = value_selected; card.show(cardpanel,"Second"); } if(e.getSource()==Select_O) { value_selected= "O"; last_value = value_selected; card.show(cardpanel,"Second"); } //end of panel 1 //second panel if(e.getSource()==FF) { FF.setLabel(last_value); FF.setEnabled(false); F_F=last_value; last(); won(); check(); } if(e.getSource()==FS) { FS.setLabel(last_value); FS.setEnabled(false); F_S=last_value; last(); won(); check(); } if(e.getSource()==FT) { FT.setLabel(last_value); FT.setEnabled(false); F_T=last_value; last(); won(); check(); } if(e.getSource()==SF) { SF.setLabel(last_value); S_F=last_value; SF.setEnabled(false); last(); won(); check(); } if(e.getSource()==SS) { SS.setLabel(last_value); SS.setEnabled(false); S_S=last_value; last(); won(); check(); } if(e.getSource()==ST) { ST.setLabel(last_value); ST.setEnabled(false); S_T=last_value; last(); won(); check(); } if(e.getSource()==TF) { TF.setLabel(last_value); TF.setEnabled(false); T_F=last_value; last(); won(); check(); } if(e.getSource()==TS) { TS.setLabel(last_value); TS.setEnabled(false); T_S=last_value; last(); won(); check(); } if(e.getSource()==TT) { TT.setLabel(last_value); TT.setEnabled(false); T_T=last_value; last(); won(); check(); } //panel 3 if(e.getSource()==Replay) { again(); } } public void last() { if(last_value.equals("X")) { last_value="O"; } else { last_value="X"; } } public void won() { //case 1 :--- horizontal line if((F_F.equals("X") && F_S.equals("X") && F_T.equals("X")) ||(F_F.equals("O") && F_S.equals("O") && F_T.equals("O"))) { card.show(cardpanel,"Third"); last(); lbl_win.setText(last_value+" WON "); } if((S_F.equals("X") && S_S.equals("X") && S_T.equals("X") ) || (S_F.equals("O") && S_S.equals("O") && S_T.equals("O"))) { card.show(cardpanel,"Third"); last(); lbl_win.setText(last_value+" WON "); } if((T_F.equals("X") && T_S.equals("X") && T_T.equals("X") ) || (T_F.equals("O") && T_S.equals("O") && T_T.equals("O"))) { card.show(cardpanel,"Third"); last(); lbl_win.setText(last_value+" WON "); } //case 2 :---- vertical line if((F_F.equals("X") && S_F.equals("X") && T_F.equals("X")) ||(F_F.equals("O") && S_F.equals("O") && T_F.equals("O"))) { card.show(cardpanel,"Third"); last(); lbl_win.setText(last_value+" WON "); } if((F_S.equals("X") && S_S.equals("X") && T_S.equals("X")) || (F_S.equals("O") && S_S.equals("O") && T_S.equals("O"))) { card.show(cardpanel,"Third"); last(); lbl_win.setText(last_value+" WON "); } if((F_T.equals("X") && S_T.equals("X") && T_T.equals("X")) || (F_T.equals("O") && S_T.equals("O") && T_T.equals("O"))) { card.show(cardpanel,"Third"); last(); lbl_win.setText(last_value+" WON "); } //case 3 : diagonal if((F_F.equals("X") && S_S.equals("X") && T_T.equals("X")) || (F_F.equals("O") && S_S.equals("O") && T_T.equals("O"))) { card.show(cardpanel,"Third"); last(); lbl_win.setText(last_value+" WON "); } if((F_T.equals("X") && S_S.equals("X") && T_F.equals("X")) || (F_T.equals("O") && S_S.equals("O") && T_F.equals("O"))) { card.show(cardpanel,"Third"); last(); lbl_win.setText(last_value+" WON "); } } public void again() { F_F="z";F_S="z";F_T="z";S_F="z";S_S="z";S_T="z";T_F="z";T_S="z";T_T="z"; FF.setEnabled(true); FS.setEnabled(true); FT.setEnabled(true); SF.setEnabled(true); SS.setEnabled(true); ST.setEnabled(true); TF.setEnabled(true); TS.setEnabled(true); TT.setEnabled(true); FF.setLabel(""); FS.setLabel(""); FT.setLabel(""); SF.setLabel(""); SS.setLabel(""); ST.setLabel(""); TF.setLabel(""); TS.setLabel(""); TT.setLabel(""); lbl_win.setText(""); card.show(cardpanel,"First"); } public void check() { if(!F_F.equals("z") && !F_S.equals("z") && !F_T.equals("z") && !S_F.equals("z") && !S_S.equals("z") && !S_T.equals("z") && !T_F.equals("z") && !T_S.equals("z") && !T_T.equals("z")) { lbl_win.setText("Draw....."); card.show(cardpanel,"Third"); } } }

Output

• actionlistener
• applet
• Game

import java.applet.Applet; import java.awt.*; import java.awt.event.*; public class calculator extends Applet implements ActionListener { Button btn1,btn2,btn3,btn4,btn5,btn6,btn7,btn8,btn9,btn0,btn_mul,btn_div,btn_min,btn_add,btn_enter,btn_decimal,btn_clr; Label lbltext; String temp1="",temp2,temp4; double temp3; boolean decimal=false,mul=false,div=false,add=false,min=false,first=true; public void init() { setForeground(Color.blue); setBackground(Color.yellow); Font font = new Font("Verdana", Font.BOLD, 20); setFont(font); setLayout(null); btn1 = new Button("1"); btn2 = new Button("2"); btn3 = new Button("3"); btn4 = new Button("4"); btn5 = new Button("5"); btn6 = new Button("6"); btn7 = new Button("7"); btn8 = new Button("8"); btn9 = new Button("9"); btn0 = new Button("0"); btn_mul = new Button("*"); btn_div = new Button("/"); btn_min = new Button("-"); btn_add = new Button("+"); btn_enter = new Button("="); btn_decimal = new Button("."); btn_clr = new Button("Clear All"); lbltext = new Label("Press Button to add value.."); add(btn1); add(btn2); add(btn3); add(btn4); add(btn5); add(btn6); add(btn7); add(btn8); add(btn9); add(btn0); add(btn_mul); add(btn_div); add(btn_min); add(btn_add); add(btn_enter); add(btn_decimal); add(lbltext); add(btn_clr); btn1.addActionListener(this); btn2.addActionListener(this); btn3.addActionListener(this); btn4.addActionListener(this); btn5.addActionListener(this); btn6.addActionListener(this); btn7.addActionListener(this); btn8.addActionListener(this); btn9.addActionListener(this); btn0.addActionListener(this); btn_mul.addActionListener(this); btn_div.addActionListener(this); btn_min.addActionListener(this); btn_add.addActionListener(this); btn_enter.addActionListener(this); btn_decimal.addActionListener(this); btn_clr.addActionListener(this); lbltext.setBounds(10,10,450,30); btn1.setBounds(10,45,50,50); btn2.setBounds(90,45,50,50); btn3.setBounds(170,45,50,50); btn_mul.setBounds(250,45,50,50); btn4.setBounds(10,125,50,50); btn5.setBounds(90,125,50,50); btn6.setBounds(170,125,50,50); btn_div.setBounds(250,125,50,50); btn7.setBounds(10,205,50,50); btn8.setBounds(90,205,50,50); btn9.setBounds(170,205,50,50); btn_min.setBounds(250,205,50,50); btn0.setBounds(10,285,50,50); btn_decimal.setBounds(90,285,50,50); btn_enter.setBounds(170,285,50,50); btn_add.setBounds(250,285,50,50); btn_clr.setBounds(10,365,250,50); }

public void actionPerformed(ActionEvent e) { if(e.getSource()==btn1) { temp1=temp1+"1"; lbltext.setText(temp1); } if(e.getSource()==btn2) { temp1=temp1+"2"; lbltext.setText(temp1); } if(e.getSource()==btn3) { temp1=temp1+"3"; lbltext.setText(temp1); } if(e.getSource()==btn4) { temp1=temp1+"4"; lbltext.setText(temp1); } if(e.getSource()==btn5) { temp1=temp1+"5"; lbltext.setText(temp1); } if(e.getSource()==btn6) { temp1=temp1+"6"; lbltext.setText(temp1); } if(e.getSource()==btn7) { temp1=temp1+"7"; lbltext.setText(temp1); } if(e.getSource()==btn8) { temp1=temp1+"8"; lbltext.setText(temp1); } if(e.getSource()==btn9) { temp1=temp1+"9"; lbltext.setText(temp1); } if(e.getSource()==btn0) { temp1=temp1+"0"; lbltext.setText(temp1); } if(e.getSource()==btn_decimal&& decimal==false) { temp1=temp1+"."; lbltext.setText(temp1); decimal=true; } if(e.getSource()==btn_clr) { decimal=false; mul=false; div=false; add=false; min=false; first=true; temp1=""; temp2=""; temp3=0; temp4=""; lbltext.setText(""); } if(e.getSource()==btn_mul) { mul=true; div=false; min=false; add=false; temp2=temp1; lbltext.setText(""); temp1=""; //if(temp4!=null){action(); } } if(e.getSource()==btn_div) { mul=false; div=true; min=false; add=false; temp2=temp1; lbltext.setText(""); temp1=""; //if(first==false){action(); } } if(e.getSource()==btn_min) { mul=false; div=false; min=true; add=false; temp2=temp1; lbltext.setText(""); temp1=""; if(first==false){action(); } first=false; } if(e.getSource()==btn_add) { mul=false; div=false; min=false; add=true; temp2=temp1; lbltext.setText(""); temp1=""; //if(first==false){action(); } first=false; } if(e.getSource()==btn_enter) { action(); } } public void action() { if(mul) { temp3 = Double.parseDouble(temp2) * Double.parseDouble(temp1); temp4=Double.toString(temp3); temp1=temp4; lbltext.setText(temp4); mul=false; div=false; min=false; add=false; } if(div) { temp3 = Double.parseDouble(temp2) / Double.parseDouble(temp1); temp4=Double.toString(temp3); temp1=temp4; lbltext.setText(temp4); mul=false; div=false; min=false; add=false; } if(min) { temp3 = Double.parseDouble(temp2) - Double.parseDouble(temp1); temp4=Double.toString(temp3); temp1=temp4; lbltext.setText(temp4); mul=false; div=false; min=false; add=false; } if(add) { temp3 = Double.parseDouble(temp2) + Double.parseDouble(temp1); temp4=Double.toString(temp3); temp1=temp4; lbltext.setText(temp4); mul=false; div=false; min=false; add=true; } } }

Output

• actionlistener
• applet