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package com.seaofnodes.simple;
import java.util.ArrayList;
public class Utils {
public static RuntimeException TODO() { return TODO("Not yet implemented"); }
public static RuntimeException TODO(String msg) { return new RuntimeException(msg); }
/**
* Fast, constant-time, element removal. Does not preserve order
*
* @param array ArrayList to modify
* @param i element to be removed
* @return element removed
*/
public static <E> void del(ArrayList<E> array, int i) {
E last = array.removeLast();
if (i < array.size()) array.set(i, last);
}
/**
* Search a list for an element by reference
*
* @param ary List to search in
* @param x Object to be searched
* @return >= 0 on success, -1 on failure
*/
public static <E> int find( ArrayList<E> ary, E x ) {
for( int i=0; i<ary.size(); i++ )
if( ary.get(i)==x )
return i;
return -1;
}
/**
* Search a list for an element by reference
*
* @param ary List to search in
* @param x Object to be searched
* @return >= 0 on success, -1 on failure
*/
public static <E> int find( E[] ary, E x ) {
for( int i=0; i<ary.length; i++ )
if( ary[i]==x )
return i;
return -1;
}
// Rotate a long, nice for hashes
public static long rot( long x, int n ) { return (x<<n) | (x>>>n); }
// Fold a 64bit hash into 32 bits
public static int fold( long x ) { return (int)((x>>32) ^ x); }
}
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