文章作者：Tyan
博客：noahsnail.com  |  CSDN  |  简书

1. Description

Max Area of Island

2. Solution

class Solution {
public:
    int maxAreaOfIsland(vector<vector<int>>& grid) {
        if(grid.size() == 0) {
            return 0;
        }
        int area = 0;
        int max_area = 0;
        int rows = grid.size();
        int columns = grid[0].size();
        for(int i = 0; i < rows; i++) {
            for(int j = 0; j < columns; j++) {
                if(grid[i][j]) {
                    area = 0;
                    getArea(grid, i, j, area, rows, columns);
                    max_area = max(area, max_area);
                }
            }
        }
        return max_area;
    }

private:
    void getArea(vector<vector<int>>& grid, int i, int j, int& area, int& rows, int& columns) {
        if(i < 0 || i == rows || j < 0 || j == columns || grid[i][j] == 0) {
            return;
        }
        grid[i][j] = 0;
        area++;
        getArea(grid, i + 1, j, area, rows, columns);
        getArea(grid, i - 1, j, area, rows, columns);
        getArea(grid, i, j + 1, area, rows, columns);
        getArea(grid, i, j - 1, area, rows, columns);
    }
};

Reference

1. https://leetcode.com/problems/max-area-of-island/description/