598. Range Addition II

598. Range Addition II (Easy)

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

Related Topics:
Math

Similar Questions:

• Range Addition (Medium)

Solution 1.

// OJ: https://leetcode.com/problems/range-addition-ii/
// Author: github.com/lzl124631x
// Time: O(L) where L is the length of `ops`
// Space: O(1)
class Solution {
public:
    int maxCount(int m, int n, vector<vector<int>>& ops) {
        for (auto &op : ops) {
            m = min(m, op[0]);
            n = min(n, op[1]);
        }
        return m * n;
    }
};