JAVA 프로그램 설계: 배열을 엄격하게 증가(LeetCode:1187)

class Solution {

    final static int inf = Integer.MAX_VALUE;

    public int makeArrayIncreasing(int[] arr1, int[] arr2) {

        int n = arr1.length;
        int m = arr2.length;
        int[][] dp = new int[n + 1][n + 1];

        for (int i = 0; i <= n; i++)
            Arrays.fill(dp[i], inf);

        Arrays.sort(arr2);

        dp[0][0] = -1;
        for (int i = 1; i <= n; i++) {
            for (int j = 0; j <= i; j++) {
                if (arr1[i - 1] > dp[i - 1][j])
                    dp[i][j] = arr1[i - 1];
                if (j > 0) {
                    int p = find(arr2, dp[i - 1][j - 1]);
                    if (p < m) dp[i][j] = Math.min(dp[i][j], arr2[p]);
                }
            }
        }

        for (int j = 0; j <= n; j++)
            if (dp[n][j] != inf)
                return j;

        return -1;

    }

    private int find(int[] arr, int val) {

        int l = 0, r = arr.length;
        while (l < r) {
            int mid = (l + r) / 2;
            if (arr[mid] > val)
                r = mid;
            else
                l = mid + 1;
        }

        return r;

    }
}