Build a pile of Cubes

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Your task is to construct a building which will be a pile of n cubes. The cube at the bottom will have a volume of n^3, the cube above will have volume of (n-1)^3 and so on until the top which will have a volume of 1^3.
You are given the total volume m of the building. Being given m can you find the number n of cubes you will have to build?
The parameter of the function findNb (find_nb, find-nb, findNb) will be an integer m and you have to return the integer n such as n^3 + (n-1)^3 + ... + 1^3 = m if such a n exists or -1 if there is no such n. Examples:
findNb(1071225) --> 45 findNb(91716553919377) --> -1
Good Solution1:
public class ASum {
  
  public static long findNb(long m) {
    long mm = 0, n = 0;
    while (mm < m) mm += ++n * n * n;
    return mm == m ? n : -1;
  }  
}

Good Solution2:
public class ASum {
  
  public static long findNb(long m) {
    long total = 0;
    int counter = 0;
    
    while (total < m) {    
      counter++;  
      total = total + (long) Math.pow(counter, 3);            
    }
    
    if (m == total)
      return counter;
    return -1;
  }  
}