#include <stdio.h>

const double PERCENT = 1.01;

int main(int argc, const char **argv)
{
    long long start = 100LL, goal = 0LL, year = 0LL;

    fscanf(stdin, "%lld", &goal);

   for ( year = 1LL;  ; year++ )
   {
       start *= PERCENT;
       if ( start >= goal ) break;
   }

    fprintf(stdout, "%lld\n", year);
    return 0;
}