题解 | #计算某字符出现次数#

const rl = require("readline").createInterface({ input: process.stdin });
var iter = rl[Symbol.asyncIterator]();
const readline = async () => (await iter.next()).value;

void async function () {
    // Write your code here
    let token = [];//while函数中的tokens是let声明，在函数外拿不到，在函数外声明一个变量拿到tokens中的数据。
    while(line = await readline()){
        // let tokens = line.split(' ');
        token.push(line); 
    }
    token[0] = token[0].toUpperCase();//字符串变成大写。.toLowerCase()//字符串变成小写
    token[1] = token[1].toUpperCase();
    // console.log(token)
    let a = 0;
    while(token[0].indexOf(token[1]) !== -1){
        a++;
        token[0] = token[0].substring(token[0].indexOf(token[1])+1,token[0].length)
	  //取token[0]中index为token[0].indexOf(token[1])+1到token[0].length的一段赋值给token[0]。
    }
    console.log(a);

}()

我的方法

void async function () {
    // Write your code here
    let result = []
    let count = 0
    while(line = await readline()){
        result.push(line)
        if( result.length == 2){
            result[0].toUpperCase().split("").forEach(el =>{			//字符串中的每个字符都单独分割。对分割后得到的数组中的每一项el都做forEach函数
               el == line.toUpperCase()?count++:''			//三目运算符
            })
            console.log(count)
        }
    }
   
}()

牛客469089949号——的方法

const rl = require("readline").createInterface({ input: process.stdin });
var iter = rl[Symbol.asyncIterator]();
const readline = async () => (await iter.next()).value;
const arr = [];
void (async function () {
  // Write your code here
  while ((line = await readline())) {
    let tokens = line.toString();//转化成字符
    arr.push(tokens.toLowerCase());
  }
  let count = 0;
  for (let k = 0; k < arr[0].length; k++) {
    if (arr[0][k] === arr[1]) {//字符串就是一个字符组成的数组，arr[0][k]的每一项都是一个字符
      count++;
    }
  }
  console.log(count);
})();

ycljy——的方法

const rl = require("readline").createInterface({ input: process.stdin });
var iter = rl[Symbol.asyncIterator]();
const readline = async () => (await iter.next()).value;

void async function () {
    // Write your code here
    let arr = []
    while(line = await readline()){
        arr.push(line.toLowerCase())
    }
    let first = arr[0]
    let second = arr[1]
    let firstArr = first.split('')
    let newArr = firstArr.filter(item => item === second)
    // let newArr = firstArr.filter(function(item){
    //     if(item === second){
    //         return item;
    //     }
    //     })
    console.log(newArr.length)
}()

牛客944083017号——的方法

const rl = require("readline").createInterface({ input: process.stdin });
var iter = rl[Symbol.asyncIterator]();
const readline = async () => (await iter.next()).value;
 
void async function () {
    // Write your code here
    let arr = []
    while(line = await readline()){
        arr.push(line.toLowerCase())
    }
    let first = arr[0]
    let second = arr[1]
    let newArr = first.split(second)//用second做分割，太聪明啦！
    console.log(newArr.length - 1)
}()

牛客944083017号——的方法2

const readline = require("readline");
 
const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout,
});
 
const arr = [];//创建一个数组，用来放输入的字符串和需要搜索的字符
rl.on('line',function (line){
    arr.push(line);
    if(arr.length === 2){
        const input = arr[0]; //这是输入的字符串
        const target = arr[1];//这是需要搜索的字符
        var res = input.match(new RegExp(target,"gim")); //res用来放所有在传入的字符串input中找到的字符target
        if(res === null) console.log(0); else console.log(res.length);//如果res为null就是没找到，否则就返回找到的个数res.length
    }                                          
});

牛客848877901号——的方法

const readline = require("readline");
const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout,
});
let arr = [];
rl.on("line", function (line) {
    const tokens = line.split(" ");
    arr.push(line);
    if(arr.length==2){
        let matchStrArr = arr[0].match(new RegExp(arr[1],'gi'));
        console.log(matchStrArr ? matchStrArr.length : 0);//三目运算符
    }
});

烤只因——的方法

2023年6月3日