#include /// /// 入力された数字を返す /// /// int ReadNum() { int negate = 0; char c = getchar(); int num = 0; int numCnt = 0; while (c != '\n') { if (c == '-') { negate = 1; } else { num = num * 10 + c - '0'; } c = getchar(); } if (negate == 1) { num *= -1; } return num; } int main() { int n = ReadNum(); int bis = 1; int cnt = 0; while (1) { bis *= 2; cnt++; if (bis >= n) break; } printf("%d\n",cnt); }