Build a pile of Cubes

Instructions
Output
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 asn^3 + (n-1)^3 + ... + 1^3 = mif such a n exists or -1 if there is no such n.

Examples:
findNb(1071225) --> 45
findNb(91716553919377) --> -1

#include"stdio.h"
#include"math.h"
int fun(int n){
    int i=1, sum=0; 
    while(sum<n){
       if(sum<n){
          sum+=pow(i, 3);
       }else if(sum==n){
          return i;
       }else{
          return -1;
       }
       printf("%d ", i);
       i++;
    }
}
main(){
   printf("%d", fun(1071225));
}