ARTS 第十一周（2019.11.25-2019.12.01）

[caimel]

Algorithm 无重复字符的最长子串

• 题目： 无重复字符的最长子串
• 思路：
  使用map来记录当前最长子串的每个字符的位置，left记录当前最长子串的起始位置，遍历数组，当遇到重复字符时（map[v] >=left），重复说明map[v]有值不等于undefined，该表达式成立，则更新该字符的位置和起始位置往后移一位。直到数组遍历一遍。

/**
 * @param {string} s
 * @return {number}
 */
var lengthOfLongestSubstring = function(s) {
    const map = {};
    let left = 0;
    
    return s.split('').reduce((max, v, i) => {
        left = map[v] >= left ? map[v] + 1 : left;
        map[v] = i;
        return Math.max(max, i - left + 1);
    }, 0);
    
};

• 结果：987 / 987 个通过测试用例
  执行用时：120 ms

Review React的immutable：改变对象没有错

https://blog.logrocket.com/immutability-in-react-ebe55253a1cc/

Tip React Native 开发实用技巧

https://www.jianshu.com/p/ccba80f34f33

Share React Native 圆形进度条组件

https://www.npmjs.com/package/react-native-circular-progress

• 实践

import React, { Component } from 'react'
import { AnimatedCircularProgress } from 'react-native-circular-progress'
import { Platform, StyleSheet, Text, View } from 'react-native'
import { scaleFontSize, scaleSize, scaleLandScapeSize } from '../../utils/screen'
import proptypes from 'prop-types'

const styles = StyleSheet.create({
    scoreContainer: {
        alignItems: 'center',
        paddingVertical: scaleSize(5),
        paddingHorizontal: scaleSize(20)
    },
    scoreText: { marginTop: scaleSize(5), fontSize: scaleFontSize(8) }
})

export default class ScoreCircle extends React.Component {
    static proptypes = {
        score: proptypes.number,
        color: proptypes.string,
        category: proptypes.string
    }
    constructor(props) {
        super(props);
        this.state = {
        }
    }
    render() {
        return (
            <View style={[styles.scoreContainer, this.props.scoreStyle]} >
                <AnimatedCircularProgress
                    size={scaleSize(80)}
                    width={scaleSize(6)}
                    lineCap='round'
                    fill={this.props.score}
                    tintColor={this.props.color}
                    backgroundColor='rgba(150,150,150,.2)' >{
                        (fill) => (
                            <Text>
                                {this.props.score + _('分')}
                            </Text>
                        )
                    }
                </AnimatedCircularProgress>
                <Text style={styles.scoreText}>
                    {this.props.category}
                </Text>
            </View>
        );
    }
}