#include <bits/stdc++.h>
int main() {
  int a, b, c, count;
  scanf("%d %d %d", &a, &b, &c);
  while (a != b) {
    if (c % a) count++;
    if (a == b) break;
    a++;
  }
  printf("%d", count);
  return 0;
}
