import java.util.*; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int q = sc.nextInt(); while(q-- > 0) { int n = sc.nextInt(); long k = sc.nextInt(); int d = 0; while(n > 0) { n -= Math.pow(k, d); if(n <= 0) break; d++; } System.out.println(d); } } }