250603 점프

public static void main(String[] args) throws Exception {
	BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
	BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
	StringBuilder sb = new StringBuilder();

	int testCaseCount = Integer.parseInt(br.readLine());
	long[] powerSum = new long[31];
	for (int i = 1; i < 31; i++) {
		powerSum[i] = (1L << i) - 1;
	}

	while (testCaseCount-- > 0) {
		StringTokenizer st = new StringTokenizer(br.readLine());
		long x = Long.parseLong(st.nextToken());
		long y = Long.parseLong(st.nextToken());
		sb.append(getMaxJumpCount(x, y, powerSum)).append('\n');
	}

	bw.write(sb.toString());
	bw.flush();
	bw.close();
	br.close();
}

private static int getMinJumpCount(long target) {
	long step = 1;
	int count = 0;
	while (target > 0) {
		target -= step;
		if (2 * step > target)
			step = 1;
		else
			step *= 2;
		count++;
	}
	return count;
}

private static int getMaxJumpCount(long left, long right, long[] powerSum) {
	if (left == right)
		return getMinJumpCount(right);
	if (left + 1 == right)
		return Math.max(getMinJumpCount(left), getMinJumpCount(right));

	int index = getPowerIndexExceeding(right, powerSum);
	if (index == 1)
		return 1;

	long jump1 = powerSum[index - 1];
	long jump2 = powerSum[index - 2];

	if (left <= jump2) {
		return Math.max((index - 2) + getMaxJumpCount(0, jump2, powerSum),
				(index - 1) + getMaxJumpCount(0, right - jump1, powerSum));
	}

	if (left > jump1) {
		return (index - 1) + getMaxJumpCount(left - jump1, right - jump1, powerSum);
	}

	if (left < jump1) {
		return Math.max((index - 2) + getMaxJumpCount(left - jump2, jump2, powerSum),
				(index - 1) + getMaxJumpCount(0, right - jump1, powerSum));
	}

	return (index - 1) + getMaxJumpCount(0, right - jump1, powerSum);
}

private static int getPowerIndexExceeding(long value, long[] powerSum) {
	for (int i = 0; i < powerSum.length; i++) {
		if (powerSum[i] > value)
			return i;
	}
	return powerSum.length;
}

출처:https://www.acmicpc.net/problem/17613