Go: package main

import "fmt"

func main() {
	var n, k int
	fmt.Scanln(&n, &k)
	height := 0
	weight := 0
	block := 1
	for n >= block {
		if weight <= k*block {
			height++
			n -= block
			weight += block
		} else {
			block++
		}
	}
	fmt.Println(height)
}

C++: #include<bits/stdc++.h>
using namespace std;
int main(){
  int n,k,x=0,sum=0,a=1;
  cin>>n>>k;
  while(1){
    if(sum>=n) break;
    sum+=a;
    if((sum-a)/a>=k){
      sum-=a; ++a; --x;
    }
    ++x;
  }
  cout<<x<<endl;
  return 0;
}

C++: #include<bits/stdc++.h>
typedef long long int ll;
typedef unsigned long long int ull;
#define BIG_NUM 2000000000
#define HUGE_NUM 99999999999999999
#define MOD 1000000007
#define EPS 0.000000001
using namespace std;


int main(){

	int N,K;
	scanf("%d %d",&N,&K);

	int ans = 1,upper = 1;
	int rest = N-1,need;

	while(true){

		if(upper%K == 0){

			need = upper/K;

		}else{

			need = (upper/K)+1;
		}

		if(need > rest){
			break;
		}

		rest -= need;
		upper += need;

		ans++;
	}

	printf("%d\n",ans);

	return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
using ll = long long;
using VI = vector<int>;
using VL = vector<ll>;
#define FOR(i,a,n) for(int (i)=(a);(i)<(n);(i)++)
#define eFOR(i,a,n) for(int (i)=(a);(i)<=(n);(i)++)
#define rFOR(i,a,n) for(int (i)=(n)-1;(i)>=(a);(i)--)
#define erFOR(i,a,n) for(int (i)=(n);(i)>=(a);(i)--)
#define SORT(i) sort((i).begin(),(i).end())
#define rSORT(i,a) sort((i).begin(),(i).end(),(a))
#define all(i) (i).begin(),(i).end()
constexpr ll INF = 1000000000;
constexpr ll LLINF = 1LL << 60;
constexpr ll mod = 1000000007;
constexpr ll MOD = 998244353;
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; }return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; }return 0; }
inline void init() { cin.tie(nullptr); cout.tie(nullptr); cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(15); }
template<class T> inline istream& operator>>(istream& input, vector<T>& v) { for (auto& elemnt : v)input >> elemnt; return input; }

int main() {
    init();
    
    int n, k;
    cin >> n >> k;

    n--;
    int sum = 1, ans = 1;
    while (1) {
        int num = sum / k + (bool)(sum % k);
        if (n < num)break;
        ans++;
        sum += num;
        n -= num;
    }
    cout << ans << "\n";
}

C++: #include<cstdio>
#include<functional>
#include<algorithm>
using namespace std;
int main(void)
{
	int n,k,x,sum,cnt;
	scanf("%d %d",&n,&k);
	cnt=1;	sum=1;	n--;
	while(1)	{
		x=sum/k+(sum%k!=0);
		if(x>n)	break;
		cnt++;	n-=x;	sum+=x;
	}
	printf("%d\n",cnt);
	return 0;
}

C++: #include<bits/stdc++.h>
#define V vector
#define VI vector<int>
#define VVI vector<vector<int>>
#define rep(i,n) for(int i=0;i<(n);i++)
#define MOD 1000000007


using namespace std;

int main(void){
    int N,K;
    cin>>N>>K;
    int t=1,n=1,a=1;
    while(1){
        n=(K+a-1)/K;
        a+=n;
        if(N<a){
            cout<<t<<endl;
            return 0;
        }
        t++;
    }
}

C++: #include <bits/stdc++.h>
using namespace std;

int main()
{
	int N, K;
	int cnt = 0;
	int num = 0;

	cin >> N >> K;

	for ( int i = 0; i < N; i++ ) {
		num++;
		if ( num * K >= N - i - 1 ) {
			num = 0;
			cnt++;
		}
	}

	cout << cnt << endl;

	return ( 0 );
}

C++: #include <iostream>
#include <iomanip>
#include <cstdio>
#include <string>
#include <cstring>
#include <deque>
#include <list>
#include <queue>
#include <stack>
#include <vector>
#include <utility>
#include <algorithm>
#include <map>
#include <set>
#include <complex>
#include <cmath>
#include <limits>
#include <cfloat>
#include <climits>
#include <ctime>
#include <cassert>
#include <numeric>
#include <fstream>
#include <functional>
#include <bitset>

using namespace std;
#define int long long int

const int INF = 1000000007;

signed main(){
    
    int n, k; cin >> n >> k;

    double sum = 0;
    int hight = 0;
    
    while(1){
        // sum に耐えうる個数のうち, 最小のものを求める
        int l = 0; 
        int r = 100010;
        while(r - l > 1){
            int d = (r + l) / 2;
            
            double w = INF;
            if(d != 0) w = sum / d;
            if(w <= k) r = d;
            else l = d;
        }

        if(r <= n){
            hight++;
            n -= r;
            sum += r;
        }else{
            cout << hight << endl;
            return 0;
        }
    }
    return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef pair<int, ll> pil;
typedef pair<int, ll> pli;
typedef pair<double,double> pdd;
#define SQ(i) ((i)*(i))
#define MEM(a, b) memset(a, (b), sizeof(a))
#define SZ(i) int(i.size())
#define FOR(i, j, k, in) for (int i=j ; i<k ; i+=in)
#define RFOR(i, j, k, in) for (int i=j ; i>=k ; i-=in)
#define REP(i, j) FOR(i, 0, j, 1)
#define REP1(i,j) FOR(i, 1, j+1, 1)
#define RREP(i, j) RFOR(i, j, 0, 1)
#define ALL(_a) _a.begin(),_a.end()
#define mp make_pair
#define pb push_back
#define eb emplace_back
#define X first
#define Y second
#ifdef tmd
#define TIME(i) Timer i(#i)
#define debug(...) do{\
    fprintf(stderr,"%s - %d (%s) = ",__PRETTY_FUNCTION__,__LINE__,#__VA_ARGS__);\
    _do(__VA_ARGS__);\
}while(0)
template<typename T>void _do(T &&_x){cerr<<_x<<endl;}
template<typename T,typename ...S> void _do(T &&_x,S &&..._t){cerr<<_x<<" ,";_do(_t...);}
template<typename _a,typename _b> ostream& operator << (ostream &_s,const pair<_a,_b> &_p){return _s<<"("<<_p.X<<","<<_p.Y<<")";}
template<typename It> ostream& _OUTC(ostream &_s,It _ita,It _itb)
{
    _s<<"{";
    for(It _it=_ita;_it!=_itb;_it++)
    {
        _s<<(_it==_ita?"":",")<<*_it;
    }
    _s<<"}";
    return _s;
}
template<typename _a> ostream &operator << (ostream &_s,vector<_a> &_c){return _OUTC(_s,ALL(_c));}
template<typename _a> ostream &operator << (ostream &_s,set<_a> &_c){return _OUTC(_s,ALL(_c));}
template<typename _a> ostream &operator << (ostream &_s,deque<_a> &_c){return _OUTC(_s,ALL(_c));}
template<typename _a,typename _b> ostream &operator << (ostream &_s,map<_a,_b> &_c){return _OUTC(_s,ALL(_c));}
template<typename _t> void pary(_t _a,_t _b){_OUTC(cerr,_a,_b);cerr<<endl;}
#define IOS()
class Timer {
private:
    string scope_name;
    chrono::high_resolution_clock::time_point start_time;
public:
    Timer (string name) : scope_name(name) {
        start_time = chrono::high_resolution_clock::now();
    }
    ~Timer () {
        auto stop_time = chrono::high_resolution_clock::now();
        auto length = chrono::duration_cast<chrono::microseconds>(stop_time - start_time).count();
        double mlength = double(length) * 0.001;
        debug(scope_name, mlength);
    }
};
#else
#define TIME(i)
#define debug(...)
#define pary(...)
#define endl '\n'
#define IOS() ios_base::sync_with_stdio(0);cin.tie(0)
#endif

const ll MOD = 1000000007;
const ll INF = 0x3f3f3f3f3f3f3f3f;
const int iNF = 0x3f3f3f3f;
// const ll MAXN = 

int n, k;
/********** Good Luck :) **********/
int main () {
    TIME(main);
    IOS();

    cin >> n >> k;
    int sum = 0, ans = 0;
    while (true) {
        int cur = max(1, (sum+k-1)/k);
        debug(cur);
        if (n < cur) {
            break;
        } else {
            n -= cur;
            sum += cur;
            ans++;
        }
    }

    cout << ans << endl;
    return 0;
}