#include<bits/stdc++.h>
using namespace std;
#define int long long
#define ii pair <int, int>
#define app push_back
#define all(a) a.begin(), a.end()
#define bp __builtin_popcountll
#define ll long long
#define mp make_pair
#define f first
#define s second
#define Time (double)clock()/CLOCKS_PER_SEC
#define debug(x) std::cout << #x << ": " << x << '\n';

const int INF = 1e18;

signed main() {
    #ifdef HOME
    freopen("input.txt", "r", stdin);
    #else
    #define endl '\n'
    ios_base::sync_with_stdio(0); cin.tie(0);          
    #endif

    int v, t, p;
    cin >> v >> t >> p;

    int full = 0;

    {
    int l = 0, r = INF;
    while (l < r - 1) {
        int m = (l + r) >> 1;
        
        int del = (m + t - 1) / t;

        if (m - del >= v * p)
            r = m;
        else
            l = m;
    }   
    full = r;
    }

    auto get = [&](int n) {
        return (n + t - 1) / t;
    };

    //after v * p secs we have 0

    int S = 0;
    if (p)
        S = full;

    int l = 0, r = INF;
    while (l < r - 1) {
        int m = (l + r) >> 1;
        
        int del = get(S+m) - get(S);

        if (m - del > v)
            r = m;
        else
            l = m;
    }   

    cout << full + l << endl;
}