nbYear.js (7kyu 16)

in about Dev on Algorithm

Codewars 알고리즘 풀이


Problem

  • In a small town the population is ‘p0 = 1000’ at the beginning of a year.
    • 첫 해의 인구는 ‘p0 = 1000’이다.
  • The population regularly increases by ‘2 percent’ per year and moreover ‘50’ new inhabitants per year come to live in the town.
    • 인구는 매년 ‘2 퍼센트’씩 증가하고, 매년 새로운 주민이 ‘50명’씩 살게 된다.
  • How many years does the town need to see its population greater or equal to ‘p = 1200’ inhabitants?
    • 인구가 ‘p = 1200’보다 크거나 같으려면 몇 년이 지나야 하는가?


Solution 01

function nbYear(p0, percent, aug, p) {
  let years = 0;
  
  while (p0 < p) {
    p0 += p0 * percent/100 + aug;
    years++;
  }
  return year;
}

nbYear(1000, 2, 50, 1200);   // 3
nbYear(1500, 5, 100, 5000);  // 15


Solution 02

function nbYear(p0, percent, aug, p) {
  if (p0 >= p) {
    return 0;
  } else {
    return 1 + nbYear(p0 + (p0 * percent) / 100 + aug, percent, aug, p);
  }
}

nbYear(1000, 2, 50, 1200);   // 3
nbYear(1500, 5, 100, 5000);  // 15