#pragma GCC optimize ("O3")
#pragma GCC target ("sse4")

#include<bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef long double ld;
typedef double db;
typedef string str;

typedef pair<int,int> pi;
typedef pair<ll,ll> pl;
typedef pair<db,db> pd;

typedef vector<int> vi; 
typedef vector<ll> vl; 
typedef vector<db> vd; 
typedef vector<str> vs; 
typedef vector<pi> vpi;
typedef vector<pl> vpl; 
typedef vector<pd> vpd; 

#define mp make_pair
#define f first
#define s second
#define sz(x) (int)(x).size()
#define all(x) begin(x), end(x)
#define rall(x) (x).rbegin(), (x).rend() 
#define rsz resize
#define ins insert 
#define ft front() 
#define bk back()
#define pf push_front 
#define pb push_back
#define eb emplace_back 
#define lb lower_bound 
#define ub upper_bound 

#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define trav(a,x) for (auto& a: x)

const int MX  = 2e5+5; 
const int MOD = 1e9+7; // 998244353;
const ll  INF = 1e18; 
const ld  PI  = acos((ld)-1);

const int xd[4] = {1,0,-1,0}, yd[4] = {0,1,0,-1};
mt19937 rng((uint32_t)chrono::steady_clock::now().time_since_epoch().count()); 

template<class T> bool ckmin(T& a, const T& b) { 
	return b < a ? a = b, 1 : 0; 
}
template<class T> bool ckmax(T& a, const T& b) { 
	return a < b ? a = b, 1 : 0; 
} 

constexpr int pct(int x) { return __builtin_popcount(x); } // number of ones 
constexpr int bits(int x) { return 31-__builtin_clz(x); } // floor(log2(x)) 
template<class T> T cdiv(T a, T b) { return a/b+!(a<0||a%b == 0); } // division of a by b rounded up, assumes b > 0 

int fstTrue(function<bool(int)> f, int lo, int hi) {
	hi++; assert(lo <= hi); // assuming f is increasing
	while (lo < hi) { // find first index such that f is true 
		int mid = (lo+hi)/2; 
		f(mid) ? hi = mid : lo = mid+1; 
	} 
	return lo;
}

template<class T> void remDup(vector<T>& v) { 
	sort(all(v)); v.erase(unique(all(v)),end(v)); 
}

// DEBUG
void DBG() { cerr << "]" << endl; }
template<class H, class... T> void DBG(H h, T... t) {
	cerr << h; if (sizeof...(t)) cerr << ", ";
	DBG(t...); 
}
#define dbg(...) cerr << "LINE(" << __LINE__ << ") -> [" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)

// FILE I/O
void setIn(str S) { freopen(S.c_str(),"r",stdin); }
void setOut(str S) { freopen(S.c_str(),"w",stdout); }
void setIO(str S = "") {
	ios_base::sync_with_stdio(0); cin.tie(0); // fast I/O
	// cin.exceptions(cin.failbit); 
	// throws exception when do smth illegal
	// ex. try to read letter into int
	if (sz(S)) { setIn(S+".in"), setOut(S+".out"); } // for USACO
}

map<ll,ll> m;
map<ll,ll> oc;

ll f(ll x, ll m) {
    return (x*x)%m;
}

int32_t main() { 
	
	setIO();

    ll N,X,M; cin >> N >> X >> M;

    bool one = 0, zero = 0;
    ll num = 0, res = 0, cycle = -1, sumc = 0, x = 1;
    FOR(i,1,N+1) {
        if (i == 1) {
            oc[X] = i; m[X] = 0;
            num = res = X;
        } else {
            ll nw = f(num,M);

            if (oc[nw]) {
                cycle = i-oc[nw];
                sumc = res-m[nw];
                num = nw;
                break;
            } else {
                oc[nw] = i;
                m[nw] = res;
            }

            res += nw; num = nw;
        }

        x = i;
    }

    if (cycle != -1) {
        ll rem = N-x; 

        res += (rem/cycle)*(sumc);
    
        ll d = rem%cycle; 
        
        FOR(i,1,d+1) {
            if (i == 1) {
                res += num;
            } else {
                ll nw = f(num,M);

                res += nw; num = nw;
            }
        }
    }

    cout << res << "\n";

}	

Measured memory_bytes: 9804