LeetCode知识点总结 - 598

LeetCode 598.Range Addition II

考点	难度
Array	Easy

题目

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.

思路

discussion里面有一个很简单的方法：先将行（r）和列（c）都设为最大值，在ops里面找最小的行数和最小的列数替换这两个值。因为operatio总是从长方形的左上角开始数，所以r和c相乘得到结果。

答案

public int maxCount(int m, int n, int[][] ops) {
        int r = m;
        int c = n;
        for(int i=0; i<ops.length; i++){
            r = Math.min(r,ops[i][0]);
            c = Math.min(c,ops[i][1]);
        }
        return r*c;
   }