网易笔试题

回文数那题，通过 80%，不知道哪里不对

import java.util.Scanner;

/**
 * Created by ivanchou on 9/12/16.
 */
public class NetEasyThree {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);

        while (in.hasNext()) {
            int n = in.nextInt();
            int[] nums = new int[n];

            for (int i = 0; i < n; i++) {
                nums[i] = in.nextInt();
            }
            System.out.println(new NetEasyThree().solve(nums));
        }
    }

    public int solve(int[] nums) {
        int count = 0;
        int p = 0, q = nums.length - 1;
        if (isPalindrome(nums, p, q)) {
            return 0;
        }

        while (p < q) {
            if (nums[p] == nums[q]) {
                p++;
                q--;
            } else if (nums[p] > nums[q]) {
                q--;
                nums[q] += nums[q + 1];
                count++;
            } else if (nums[p] < nums[q]) {
                p++;
                nums[p] += nums[p - 1];
                count++;
            }
            if (isPalindrome(nums, p, q)) {
                return count;
            }
        }
        return count;
    }

    public boolean isPalindrome(int[] nums, int p, int q) {
        // 数组长度为 0 或者 1 本身就是回文数列
        int length = q - p + 1;
        if (length == 0 || length == 1) {
            return true;
        }

        // 数组长度为 2 最多执行一次操作
        if (length == 2) {
            if (nums[p] != nums[q]) {
                return false;
            } else {
                return true;
            }
        }

        int i = p;
        for (; i < (q + 1) / 2; i++) {
            if (nums[i] != nums[q - i]) {
                break;
            }
        }
        if (i >= (q + 1) / 2) {
            return true;
        } else {
            return false;
        }
    }
}