public class application{
public static void main (String args[]){
for(int i=0;i<4;i++){
for(int j=0;j<=i;j++){
System.out.print("@");
}
System.out.println("");
}
}
}


import java.awt.*;

public class applet extends java.applet.Applet {
String ss = "@";
int y = 50;
public void paint(Graphics g) {

for(int j=0;j<=i;j++){
g.drawString(ss,50,y);
ss = ss+"@";
y = y+10;
}
}
}