leetcode807. 保持城市天际线(java)

贪心思想

class Solution {
    public int maxIncreaseKeepingSkyline(int[][] grid) {
        int ans =0;
        int n = grid.length;
        int[] rol = new int[n];
        int[] col = new int[n];
        for(int i = 0; i < n; i ++){
            for(int j = 0; j < n; j ++){
                rol[i] = Math.max(rol[i], grid[i][j]);
                col[j] = Math.max(col[j], grid[i][j]);
            }
        }

        for(int i = 0; i < n; i ++){
            for(int j = 0; j < n; j ++){
                ans += Math.min(rol[i], col[j]) - grid[i][j];
            }
        }
        return ans;
    }
}