找找第k个数在第几堆里

/**     * 找找第k个数在第几堆里，例如：     * int k = 25;     * int[] array = new int[]{10, 12, 14, 15};     * 答案是 3 .     *     * @param heaps     * @param k     * @return     */    public static int whereAmI(int[] heaps, int k) {        if (null == heaps || 0 == heaps.length || 0 >= k) {            return -1;        }        int[] heapRecord = new int[heaps.length];        int sum = 0;        for (int i = 0; i < heaps.length; i++) {            sum += heaps[i];            heapRecord[i] = sum;        }        if (k > sum) {            return -1;        }        return 1 + whereAmI(heapRecord, 0, heaps.length - 1, k);    }    private static int whereAmI(int[] heapRecord, int start, int end, int k) {        if (start >= end) {            return start;        }        int mid = start + (end - start) / 2;        if (heapRecord[mid] == k) {            return mid;        }        if (heapRecord[mid] < k) {            return whereAmI(heapRecord, mid + 1, end, k);        }        return whereAmI(heapRecord, start, mid - 1, k);    }