贝克第四题

求大佬帮看看有什么问题，82%，

思路就是，用4个前缀数组，做一个递增的，一个递减的序列，然后更新min值找最小

import java.util.Scanner;

public class Main {

  public static void main(String[] args) {

    Scanner input = new Scanner(System.in);

    int n = input.nextInt();

    int[] nums = new int[n];

    for(int i = 0;i<n;i++)

      nums[i] = input.nextInt();

    System.out.println(minAdd(nums));

  }

  public static int minAdd(int[] nums) {

    int n = nums.length;

    int[] i_mods = new int[n];

    int[] d_mods = new int[n];

    int[] i_maxs = new int[n];

    int[] d_maxs = new int[n];

    for (int i = 0; i < n; i++) {

      if (i == 0) {

        i_mods[i] = 0;

        i_maxs[i] = nums[i];

        continue;

      }

      int max = Math.max(nums[i], i_maxs[i - 1] + 1);

      i_mods[i] = max - nums[i] + i_mods[i - 1];

      i_maxs[i] = max;

    }

    for (int i = n - 1; i >= 0; i--) {

      if (i == n - 1) {

        d_mods[i] = 0;

        d_maxs[i] = nums[i];

        continue;

      }

      int max = Math.max(nums[i], d_maxs[i + 1] + 1);

      d_mods[i] = max - nums[i] + d_mods[i + 1];

      d_maxs[i] = max;

    }

    int min = Integer.MAX_VALUE;

    for (int i = 0; i < n; i++) {

      int mod = i_mods[i] + d_mods[i] - (Math.min(i_maxs[i], d_maxs[i]) - nums[i]);

      min = Math.min(mod, min);

    }

    min = Math.min(i_mods[n-1],min);

    min = Math.min(d_mods[0],min);

    return min;

  }

}