Error in extracting digits from integer

I have a simple program which gives the wrong output, the expected output is the digits of the number.

#include <iostream>
#include <cstdio>
#include <cmath>
#include <cstdlib>


using namespace std;

int main()
{
   int n = 125521;
   int d = floor(log10(n));
   printf("%d Digits\n",d+1);
   int t =0;
   while(floor(log10(n))-t)
   { printf("%d-----%d\n",(n/(int)pow(10,floor(log10(n))-t)%10),t); t++;}
   return 0;
}

This gives the output

6 Digits
1-----0
2-----1
5-----2
7-----3
2-----4

Strange output. Why does 7 come ?

I know how to get the digits by other ways but I want this solution to work.

Now as suggested in the answers I get rid of the bug in the while loop (>=0) and I get the output: