Range Addition II

Similar Problems:

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 = 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:

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

Github: code.dennyzhang.com

Credits To: leetcode.com

Leave me comments, if you have better ways to solve.

## https://code.dennyzhang.com/range-addition-ii ## Basic Ideas: The biggest number will happen in the left-corner ## min(ops_i) * min(ops_j) ## ## Complexity: Time O(len(ops)), Space O(1) class Solution(object): def maxCount(self, m, n, ops): """ :type m: int :type n: int :type ops: List[List[int]] :rtype: int """ min_i, min_j = m, n for (i, j) in ops: min_i = min(i, min_i) min_j = min(j, min_j) return min_i*min_j