题解 | #计算某字符出现次数#

const rl = require("readline").createInterface({ input: process.stdin });

let arr = [];

rl.on("line", function(line) {
    arr.push(line);
    // console.log(arr)
    let count = 0;
    
    if (arr.length == 2) {
        let [input, str] = arr;
        str = str.toLowerCase();
        let input_arr = input.split("");
        for (let i = 0; i < input_arr.length; i++) {
            if (input_arr[i].toLowerCase() == str) {
                count++;
            }
        }
        
        console.log(count);
    }
})