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public class trys {
public static String upcase(String s){
return s.toUpperCase();
}
public static void main(String[] args) {
String q="howdy";
System.out.println(q);
String qq=upcase(q);
System.out.println(qq);
System.out.println(q);
}
}
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String s="asdf";
String x=Immutable.upcase(s);
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public class Concatenation{
public static void main(String[] args){
String mango="mango";
String s="abc"+mango+"def"+47;
System.out.println(s);
}
}
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public class HelloWorld
{
public static void main(String[] argv){
try{
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