#include <stdio.h>


int main(void){
    unsigned long int x = -1;
    scanf("%lu\n", &x);

    if (x == -1){
        printf("Error in scan");
        return 1;
    }
    
  	unsigned long int money = 100;
    for(int year = 0; year < 3763; year++){
        if (money >= x){
            printf("%d\n", year);
            break;
        }
        money *= 1.01;
    }

    return 0;
}