Given an m * n matrix M initialized with all 0's and several update operations.

Operations are represented by a 2D array, and each operation is represented by an array with two positive integers a and b, which means M[i][j] should be added by one for all 0 <= i < a and 0 <= j < b.

You need to count and return the number of maximum integers in the matrix after performing all the operations.

Example 1:

Input: m = 3, n = 3operations = [[2,2],[3,3]]Output: 4Explanation: Initially, M = [[0, 0, 0], [0, 0, 0], [0, 0, 0]]After performing [2,2], M = [[1, 1, 0], [1, 1, 0], [0, 0, 0]]After performing [3,3], M = [[2, 2, 1], [2, 2, 1], [1, 1, 1]]So the maximum integer in M is 2, and there are four of it in M. So return 4. 模拟会空间复杂度会超，必须直接计算。计算重叠部分。

class Solution {    public int maxCount(int m, int n, int[][] ops) {        if (ops == null || ops.length <=0 || ops[0].length <= 0)            return m*n;        int minX = Integer.MAX_VALUE, minY = Integer.MAX_VALUE;        for (int i=0; i
     
       p)                minX = p;            if (minY > q)                minY = q;        }        return minX * minY;    }}