#include <stdio.h>
#include <iostream>

class Yuki
{
public:
  long long int old;
  long long int sum;
  long long int start;
  long long int end;
  long long int middle;

};

void BinarySearch(Yuki *yuki, long long int a_num, long long int b_get, long long int c)
{
  while(1){
    long long int n_get = yuki->middle / a_num;
    yuki->sum = b_get * n_get + (yuki->middle - n_get);
    /*
    printf("%lld %lld %lld\n", yuki->sum, n_get, yuki->middle-n_get);
    exit(0);
    */
    if(yuki->sum < c && yuki->sum > 0){
     if(yuki->middle == yuki->start){
      yuki->old = yuki->end;
      break;
    }
    yuki->start = yuki->middle;
    yuki->middle = (yuki->end + yuki->middle) / 2;
    //printf("%lld 1\n", yuki->middle);
  } else if(yuki->sum > c || yuki->sum < 0){
    if(yuki->middle == yuki->end){
    yuki->old = yuki->start;
    break;
  }
    yuki->end = yuki->middle;
    yuki->middle = (yuki->start + yuki->end) / 2;
  //printf("%lld 2\n", yuki->middle);
  } else {
    yuki->old = yuki->middle;
      //printf("%lld\n", yuki.old);
    break;
  }
}
}


int main(void)
{
  long long int a_num, b_get, c; 

  scanf("%lld %lld %lld", &a_num, &b_get, &c);

  
  Yuki yuki;
  yuki.sum=0;
  yuki.old = 1;
  yuki.start = 1;
  yuki.end = c;
  
  if(c == 1){
    yuki.middle = 1;
  } else {
    yuki.middle = c / 2;
  }

  BinarySearch(&yuki, a_num, b_get, c);

  printf("%lld\n", yuki.old);

  return 0;
}