#include <stdio.h>
int main(void){
    // Your code here!
    
    unsigned long long int money = 100, target;
    
    scanf("%llu", &target);
    
    for(unsigned long long int i = 1; ; i++){
        money = money * 1.01;
        if(money >= target){
            printf("%llu\n", i);
            break;
        }
    }
    
}
