#include<stdio.h>



int FindX(int n)
{
    int sum, count;
    for(int j = 1; sum <= n;j++)
  {
    sum = sum + j;
        if(sum > n)
        {
        break;
        }
    count = count + 1;
  }
  return count;
}
void main()
{
int n;
    printf("enter n: ");
  do
   {
     scanf("%d", &n);
     if(n < 0)
       {
         printf("n must greater than 0")
       }
   }while(n < 0)
    
    printf("X = %d", FindX(n));
    getch();
}