개발야옹

https://www.acmicpc.net/problem/18108

const fs = require('fs');
let input = fs.readFileSync('/dev/stdin').toString().trim();

console.log(Number(input) - 543);

https://www.acmicpc.net/problem/25304

const fs = require('fs');
const input = fs.readFileSync('/dev/stdin').toString().split('\n');

const total = Number(input[0]);
const number = Number(input[1]);

let add = 0;

for(let i = 0 ; i < number; i++) {
    const [price, n] = input[i+2].split(" ");
    add += Number(price) * Number(n);
}

if(add === total) console.log('Yes');
else console.log("No");

https://www.acmicpc.net/problem/1110

const fs = require('fs');
const input = fs.readFileSync('/dev/stdin').toString().trim();

const T = Number(input);
let cnt = 1;
let N = input.split("");
let M = 0;

N.forEach((n) => {
    M += Number(n);
});

M = M.toString().split("");
let W = N[N.length-1].concat(M[M.length-1]);

while(true) {
    if(Number(W) === T) break;
    N = W.split("");
    M = 0;
    N.forEach((n) => {
        M += Number(n);
    });
    M = M.toString().split("");
    W = N[N.length-1].concat(M[M.length-1]);
    cnt++;
}
console.log(cnt);