598. Range Addition II 范围相加

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 meansM[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 = 3
operations = [[2,2],[3,3]]
Output: 4
Explanation: 
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.

Note:

1. The range of m and n is [1,40000].
2. The range of a is [1,m], and the range of b is [1,n].
3. The range of operations size won't exceed 10,000.

题意：给定一个m*n的矩阵，把数组初始化为0，然后用ops二维数组去更新矩阵的每个元素值，例如a=2,b=2则矩阵M11-M22全部增加1，以此类推，然后找出最大的元素的个数。

解法：寻找到被操作次数最多的行和列

public class Solution {
    public int MaxCount(int m, int n, int[,] ops) {
		int rowMin = Int32.MaxValue;
		int colMin = Int32.MaxValue;
		if (ops.GetLength(0) == 0) {
			return m * n;
		}
		for (int i = 0; i < ops.GetLength(0); i++) {
			int row = ops[i, 0];
			int col = ops[i, 1];
			if (row > 0) {
				rowMin = Math.Min(rowMin, row);
			} else {
				return 0;
			}
			if (col > 0) {
				colMin = Math.Min(colMin, col);
			}else {
				return 0;
			}
		}
		return rowMin * colMin;
	}
}

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