zoukankan      html  css  js  c++  java
  • 832. Flipping an Image

    Given a binary matrix A, we want to flip the image horizontally, then invert it, and return the resulting image.

    To flip an image horizontally means that each row of the image is reversed. For example, flipping [1, 1, 0] horizontally results in [0, 1, 1].

    To invert an image means that each 0 is replaced by 1, and each 1 is replaced by 0. For example, inverting [0, 1, 1] results in [1, 0, 0].

    Example 1:

    Input: [[1,1,0],[1,0,1],[0,0,0]]
    Output: [[1,0,0],[0,1,0],[1,1,1]]
    Explanation: First reverse each row: [[0,1,1],[1,0,1],[0,0,0]].
    Then, invert the image: [[1,0,0],[0,1,0],[1,1,1]]
    Example 2:

    Input: [[1,1,0,0],[1,0,0,1],[0,1,1,1],[1,0,1,0]]
    Output: [[1,1,0,0],[0,1,1,0],[0,0,0,1],[1,0,1,0]]
    Explanation: First reverse each row: [[0,0,1,1],[1,0,0,1],[1,1,1,0],[0,1,0,1]].
    Then invert the image: [[1,1,0,0],[0,1,1,0],[0,0,0,1],[1,0,1,0]]
    Notes:

    1 <= A.length = A[0].length <= 20
    0 <= A[i][j] <= 1

    思路:
    由题意可知,需要将二维数组中的每一行逆序,然后将二维数组中的全部元素如果是0,则置1,如果是1,则置0。


    
    class Solution {
    public:
        void swap(int& a, int& b) {
            int tmp;
            tmp = a;
            a = b;
            b = tmp;
        }
        
        vector<vector<int>> flipAndInvertImage(vector<vector<int>>& A) {
            if(A[0].size() > 20) return A;
            int len = A[0].size();
            //int half_len = A[0].size() << 1;
            // flip
            for(int i = 0; i < len; ++i) {
                for(int l = 0, h = len-1; l < h; ++l, --h) {
                    if(A[i][l] >= 0 && A[i][l] <= 1
                      && A[i][h] >= 0 && A[i][h] <= 1) {
                        swap(A[i][l], A[i][h]);
                    } else {
                        return A;
                    }
                    
                }
                
            }
            
            // invert
            for(int i = 0; i < len; ++i) {
                for (int j = 0; j < len; ++j) {
                    if(A[i][j] == 0) A[i][j] = 1;
                    else A[i][j] = 0;
                }
            }
            return A;
        }
    };
    
    
    转载本Blog文章请注明出处,否则,本作者保留追究其法律责任的权利。 本人转载别人或者copy别人的博客内容的部分,会尽量附上原文出处,仅供学习交流之用,如有侵权,联系立删。
  • 相关阅读:
    Symfony2 学习笔记之报错
    Symfony2学习笔记之数据校验
    Symfony2学习笔记之HTTP Cache
    Symfony2学习笔记之表单
    Symfony2 学习笔记之插件格式
    Symfony2学习笔记之数据库操作
    Symfony2 学习笔记之内部构件
    Symfony2 学习笔记之模板使用
    让VIEWSTATE从页面中完全消失(小技巧)
    打包bat等文件成exe,双击运行不显示dos窗口,exe不报毒
  • 原文地址:https://www.cnblogs.com/drfxiaoliuzi/p/9203156.html
Copyright © 2011-2022 走看看