You are given an m x n matrix M initialized with all 0's and an array of operations ops, where ops[i] = [ai, bi] means M[x][y] should be incremented by one for all 0 <= x < ai and 0 <= y < bi. Count and return the number of maximum integers in the matrix after performing all the operations. Example 1: Input: m = 3, n = 3, ops = [[2,2],[3,3]] Output: 4 Explanation: The maximum integer in M is 2, and there are four of it in M. So return 4. Example 2: Input: m = 3, n = 3, ops = [[2,2],[3,3],[3,3],[3,3],[2,2],[3,3],[3,3],[3,3],[2,2],[3,3],[3,3],[3,3]] Output: 4 Example 3: Input: m = 3, n = 3, ops = [] Output: 9 Constraints: 1 <= m, n <= 4 * 104 1 <= ops.length <= 104 ops[i].length == 2 1 <= ai <= m 1 <= bi <= n