#include<bits/stdc++.h>
#include<atcoder/all>
using namespace std;
using namespace atcoder;
typedef long long int ll;
typedef long double ld;
typedef vector<ll> vi;
typedef vector<vi> vvi;
typedef vector<vvi> vvvi;
typedef vector<vvvi> vvvvi;
typedef pair<ll,ll> pi;
typedef pair<ll,pi> ppi;
typedef pair<ll,ppi> pppi;
typedef pair<ll,pppi> ppppi;
#define FOR(i,l,r) for(ll i=l;i<r;i++)
#define REP(i,n) FOR(i,0,n)
#define RFOR(i,l,r) for(ll i=r-1;i>=l;i--)
#define RREP(i,n) RFOR(i,0,n)
#define ALL(x) x.begin(),x.end()
#define F first
#define S second
#define BS(A,x) binary_search(ALL(A),x)
#define LB(A,x) (ll)(lower_bound(ALL(A),x)-A.begin())
#define UB(A,x) (ll)(upper_bound(ALL(A),x)-A.begin())
#define COU(A,x) (UB(A,x)-LB(A,x))
#define sz(c) ((ll)(c).size())
template<typename T>using min_priority_queue=priority_queue<T,vector<T>,greater<T>>;
template<typename T1,typename T2>ostream&operator<<(ostream&os,pair<T1,T2>&p){os<<p.F<<" "<<p.S;return os;}
template<typename T1,typename T2>istream&operator>>(istream&is,pair<T1,T2>&p){is>>p.F>>p.S;return is;}
template<typename T>ostream&operator<<(ostream&os,vector<T>&v){REP(i,sz(v))os<<v[i]<<(i+1!=sz(v)?" ":"");return os;}
template<typename T>istream&operator>>(istream&is,vector<T>&v){for(T&in:v)is>>in;return is;}
template<class T>bool chmax(T&a,T b){if(a<b){a=b;return 1;}return 0;}
template<class T>bool chmin(T&a,T b){if(b<a){a=b;return 1;}return 0;}
ld dist(ld x1,ld y1,ld x2,ld y2){return sqrtl((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));}
/*
using mint=modint998244353;
const ll mod=998244353;
//*/
/*
using mint=modint1000000007;
const ll mod=1000000007;
//*/
//using mint=modint;
/*
typedef vector<mint> vm;
typedef vector<vm> vvm;
typedef vector<vvm> vvvm;
typedef vector<vvvm> vvvvm;
ostream&operator<<(ostream&os,mint&a){os<<a.val();return os;}
//*/
vector<pi>K(2e6);
vi _K(2e6);
pi ex(ll N,ll p,ll M){
  if(N<M)return K[N];
  pi x=ex(N/p,p,M);
  x.S+=N/p;
  x.F*=pow_mod(_K[M-1],N/M,M)*_K[N%M]%M;
  x.F%=M;
  return x;
}
ll solve(ll L,ll R,ll p,ll M){
  K[0]=pi(1,0);
  FOR(i,1,M){
    K[i]=K[i-1];
    ll j=i;
    while(j%p==0){K[i].S++;j/=p;}
    K[i].F*=j;
    K[i].F%=M;
  }
  _K[0]=1;
  FOR(i,1,M){
    _K[i]=_K[i-1];
    if(i%p)_K[i]=_K[i]*i%M;
  }
  ll ans=0;
  pi x=ex(2*L,p,M),y=ex(L,p,M);
  y.F=inv_mod(y.F,M);
  x.F=x.F*y.F%M*y.F%M;
  x.S-=2*y.S;
  //cout<<x.F<<" * "<<p<<" ^ "<<x.S<<endl;
  FOR(n,L,R+1){
    ans+=x.F*pow_mod(p,x.S,M)%M;
    ans%=M;
    ll a=4*n+2;
    while(a%p==0){x.S++;a/=p;}
    x.F*=a%M;
    ll b=n+1;
    while(b%p==0){x.S--;b/=p;}
    x.F*=inv_mod(b,M)%M;
    x.F%=M;
  }
  ans%=M;
  if(ans<0)ans+=M;
  return ans;
}
int main(){
  ll L,R,M;cin>>L>>R>>M;
  ll _M=M;
  vi m,r;
  ll d=2;
  while(d*d<=M){
    if(M%d==0){
      ll c=d;
      while(M%c==0)c*=d;
      c/=d;
      m.emplace_back(c);
      r.emplace_back(solve(L,R,d,c));
      M/=c;
    }
    d++;
  }
  if(M>1){
    m.emplace_back(M);
    r.emplace_back(solve(L,R,M,M));
  }
  ll ans=crt(r,m).F;
  ans-=2*(R-L+1);
  ans%=_M;
  if(ans<0)ans+=_M;
  cout<<ans<<endl;
  return 0;
}