zoukankan      html  css  js  c++  java
  • 246. Strobogrammatic Number

    A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down).

    Write a function to determine if a number is strobogrammatic. The number is represented as a string.

    For example, the numbers "69", "88", and "818" are all strobogrammatic.246. Strobogrammatic Number

    public class Solution {
        public boolean isStrobogrammatic(String nums) {
            // 6 - > 9 , 9 - > 6 , 1 - > 1, 8 - > 8, 0 -> 0
            int array[] = {0, 1, 0, 0, 0, 0 ,9, 0, 8, 6};
            String res = "";
            for(int i = nums.length() - 1 ; i >= 0; i--){
                if(nums.charAt(i) - '0' >= 0 && nums.charAt(i) - '0' <= 9 ){
                    res = res + array[nums.charAt(i) - '0'] ;
                }
                else
                    return false;
            }
            return res.equals(nums);
        } 
        
        //2 pointer O(n/2) ---method 2
        public boolean isStrobogrammatic(String nums) {
            int i = 0;
            int j = nums.length() - 1;
            while(i <= j){
               if(isPair(nums.charAt(i), nums.charAt(j))){
                   i++;
                   j--;
               }
               else return false;
            }
            return true;
        }
        public boolean isPair(char num1 , char num2){
            if(num1 == '6' && num2 == '9' ||
            num1 == '9' && num2 == '6' || 
            num1 == '8' && num2 == '8' ||
            num1 == '1' && num2 == '1'||
            num1 == '0' && num2 == '0')  
                return true;
            else
                return false;
        }
    }
  • 相关阅读:
    css子元素水平垂直居中
    js 防抖节流
    NOIP 游记
    flash player播放器用法
    android设备连接不上电脑的解决方法
    AndroidStudio自动下载gradle失败问题解决
    3组Alpha冲刺5/6
    3组Beta冲刺2/5
    3组Beta冲刺5/5
    3组Beta冲刺1/5
  • 原文地址:https://www.cnblogs.com/joannacode/p/5965885.html
Copyright © 2011-2022 走看看