import java.util.HashMap;
import java.util.Map;
public class Main {
/**
* Clones the lhs map and add all things from the
* rhs map.
*
* @param lhs the first map
* @param rhs the second map
* @return the merged map
*/
public static Map merge(Map lhs, Map rhs) {
Map result = null;
if((lhs == null) || (lhs.size() == 0)) {
result = copy(rhs);
}
else if((rhs == null) || (rhs.size() == 0)) {
result = copy(lhs);
}
else {
result = copy(lhs);
result.putAll(rhs);
}
return result;
}
/**
* Clones a map.
*
* @param source the source map
* @return the clone of the source map
*/
public static Map copy(Map source) {
if(source == null) {
return null;
}
Map result = new HashMap();
result.putAll(source);
return result;
}
}