C :

#include<stdio.h>
int main()
{
	int VUL,D;
	while(scanf("%d%d",&VUL,&D)!=EOF)
	{
		int i=1,t=0,s=0,count=0;
		while(1)
		{
			s+=i*D;
			count+=i;
			if(s==VUL)
			{
				t=count+i-1;
				break;
			}
			if((s+(i+1)*D)>VUL)
			{
				int d;
				d=(VUL-s)%D?((VUL-s)/D+1):(VUL-s)/D;
				t=count+i+d;
				break;
			}
			else i++;
		}
		printf("%d\n",t);
	}
	return 0;
}

C++ :

#include<iostream>
#include<cstdio>
#include<cstring>
#include<map>
#include<queue>
#include<stack>
#include<set>
#include<vector>
#include<algorithm>
#include<cmath>
using namespace std;
#define Max(a,b) (a > b ? a : b)
#define Min(a,b) (a < b ? a : b)
#define INF 0x3f3f3f3f
#define M 100

int judge(double n ,double d)
{
    double ans = 0;
    for(int i = 1; ; i++)
    {
        ans += i * d;
        if(ans >= n)
        {
            return i;
        }
    }
}

int main()
{
    double n,d;
    while(scanf("%lf%lf",&n,&d)!=EOF)
    {
        int ans = n / d + 0.9;
        ans += judge(n,d) - 1;
        printf("%d\n",ans );
    }
    return 0;
}

Pascal :

program p1022;
var s,i,j,k,t:longint;
    vul,d:longint;
begin
  while not eof do
  begin
     readln(vul,d);
     s:=0; i:=0; t:=0;
     t:=vul div d;
     if d*t<vul then t:=t+1;
     while s<t do
      begin
        i:=i+1;  
        s:=s+i;
      end;
     writeln(t+i-1)
  end;
end.

Java :

import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		while(in.hasNext()){
			int vul = in.nextInt();
			int d = in.nextInt();
			int[] arr = new int[200];
			arr[0] = d;
			for(int i=1;i<arr.length;i++){
				int tem =(i+1)*d;  
				arr[i] = arr[i-1]+tem;
				if(vul<=arr[i]){
					if(d==arr[i])System.out.println(i+1+(vul+d-1)/d);
					else System.out.println(i+(vul+d-1)/d);
					break;
				}
			}
		}
	}

}

Python :

import sys,math
  
def check(n,d):
    Alist=[]
    j = int((2*n/d)**0.5+1)
    for i in xrange(1,j):
        if (i+1)*i*d <= 2*n:
            Alist.append(i)  
    k= max(Alist)
    if 2*n-k*(k+1)*d==0:
        print (k+1)*k/2+(k-1)
    elif n%d == 0:
        l = math.ceil(n/d-k*(k+1)/2)
        print k*(k+1)/2+k+int(l)
    else:
        l = math.ceil(n/d-k*(k+1)/2+1)
        print k*(k+1)/2+k+int(l)

for line in sys.stdin:
    n,d = map(lambda x:int(x),line.split())
    check(n,d)

C# :

using System;
using System.Collections.Generic;

namespace BoP
{
    class Program
    {

        static void Main(string[] args)
        {
            string line;
            while ((line = Console.ReadLine()) != null)
            {
                string[] tokens = line.Split(' ');
                int a = int.Parse(tokens[0]);
                int b = int.Parse(tokens[1]);
                int sum = a / b;
                if (a % b != 0)
                {
                    sum++;
                }
                int z = 1;
                int x = 0;
                while (x < sum)
                {
                    x += z;
                    z++;
                }
                z--;
                z--;
                int sdfds = z;
                int sdfdssdfsf = sdfds + sum;
                Console.WriteLine(sdfdssdfsf);
            }
        }
    }
}