#include<iostream>
#include<string>
#include <cstdlib>
#include <algorithm>
#include<cmath>
#include<cstring>
#include<cstdio>
#include<vector>
#include<queue>
#include <assert.h>
#include<map>
#include<set>
#include<bitset>
#include <iomanip>
#include<stack>
#include <unordered_map>
#include<cmath>
using namespace std;
#pragma comment(linker, "/STACK:1024000000,1024000000")
// #define pi acos(-1)
// #include<bits/stdc++.h>
typedef long long ll;
#define INF 0x7f7f7f7f //2139062143
#define INF1 0x3f3f3f3f //1061109567
#define INF2 2147483647
#define llINF 9223372036854775807
#define pi 3.14159265358979323846264338327950254
#define pb push_back
#define ll long long
#define debug cout << "debug\n";
#define STDIN freopen("in.txt","r",stdin); freopen("out.txt","w",stdout);//************************************
#define Quick ios::sync_with_stdio(false);cin.tie(NULL);
#define scai(x) scanf("%d", &x)
#define sca2i(x, y) scanf("%d %d", &x, &y)
#define scaf(x) scanf("%lf", &x)
#define sca2f(x, y) scanf("%lf %lf", &x, &y)
#define For(m,n) for (int i = m;  i < n; i++)
#define PII pair<int,int>
#define PLL pair<long, long>
#define ft first
#define sd second
#define pb push_back


const int maxn=333333,mod=1000000009;
#define lson o<<1,l,mid
#define rson o<<1|1,mid+1,r
#define FOR(i,a,b) for(int i=(a);i<=(b);i++)
#define ROF(i,a,b) for(int i=(a);i>=(b);i--)
#define MEM(x,v) memset(x,v,sizeof(x))

inline int read(){
    char ch=getchar();int x=0,f=0;
    while(ch<'0' || ch>'9') f|=ch=='-',ch=getchar();
    while(ch>='0' && ch<='9') x=x*10+ch-'0',ch=getchar();
    return f?-x:x;}
 

double qmi(double m, int k)
{
    double res = 1;
    double t = m;
    while (k)
    {
        if (k&1) res = res * t;
        t = t * t;
        k >>= 1;
    }
    return res;
}
 int main()
 {
     //STDIN

     ll n;
     cin >> n;
    //  cout << n << endl;
    ll sum = 100;
     for (int i = 1; i <= 5000; i++)
     {
        //  cout << i << " " <<(ll)100*qmi(1.01,i) << endl;
        sum *=1.01;
         if (sum >= n)
         {
             cout << i << endl;
             return 0;
         }
     }
     
 }