import std.conv, std.functional, std.range, std.stdio, std.string;
import std.algorithm, std.array, std.bigint, std.bitmanip, std.complex, std.container, std.math, std.mathspecial, std.numeric, std.regex, std.typecons;
import core.bitop;

class EOFException : Throwable { this() { super("EOF"); } }
string[] tokens;
string readToken() { for (; tokens.empty; ) { if (stdin.eof) { throw new EOFException; } tokens = readln.split; } auto token = tokens.front; tokens.popFront; return token; }
int readInt() { return readToken.to!int; }
long readLong() { return readToken.to!long; }
real readReal() { return readToken.to!real; }

bool chmin(T)(ref T t, in T f) { if (t > f) { t = f; return true; } else { return false; } }
bool chmax(T)(ref T t, in T f) { if (t < f) { t = f; return true; } else { return false; } }

int binarySearch(alias pred, T)(in T[] as) { int lo = -1, hi = cast(int)(as.length); for (; lo + 1 < hi; ) { const mid = (lo + hi) >> 1; (unaryFun!pred(as[mid]) ? hi : lo) = mid; } return hi; }
int lowerBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a >= val)); }
int upperBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a > val)); }


struct ModInt {
  static int M;
  import std.conv : to;
  uint x;
  this(ModInt a) { x = a.x; }
  this(uint x_) { x = x_ % M; }
  this(ulong x_) { x = cast(uint)(x_ % M); }
  this(int x_) { x = ((x_ %= cast(int)(M)) < 0) ? (x_ + cast(int)(M)) : x_; }
  this(long x_) { x = cast(uint)(((x_ %= cast(long)(M)) < 0) ? (x_ + cast(long)(M)) : x_); }
  ref ModInt opAssign(T)(inout(T) a) if (is(T == uint) || is(T == ulong) || is(T == int) || is(T == long)) { return this = ModInt(a); }
  ref ModInt opOpAssign(string op, T)(T a) {
    static if (is(T == ModInt)) {
      static if (op == "+") { x = ((x += a.x) >= M) ? (x - M) : x; }
      else static if (op == "-") { x = ((x -= a.x) >= M) ? (x + M) : x; }
      else static if (op == "*") { x = cast(uint)((cast(ulong)(x) * a.x) % M); }
      else static if (op == "/") { this *= a.inv(); }
      else static assert(false);
      return this;
    } else static if (op == "^^") {
      if (a < 0) return this = inv()^^(-a);
      ModInt b = this, c = 1U;
      for (long e = a; e; e >>= 1) { if (e & 1) c *= b; b *= b; }
      return this = c;
    } else {
      return mixin("this " ~ op ~ "= ModInt(a)");
    }
  }
  ModInt inv() const {
    uint a = M, b = x; int y = 0, z = 1;
    for (; b; ) { const q = a / b; const c = a - q * b; a = b; b = c; const w = y - cast(int)(q) * z; y = z; z = w; }
    assert(a == 1); return ModInt(y);
  }
  ModInt opUnary(string op)() const {
    static if (op == "+") { return this; }
    else static if (op == "-") { ModInt a; a.x = x ? (M - x) : 0U; return a; }
    else static assert(false);
  }
  ModInt opBinary(string op, T)(T a) const { return mixin("ModInt(this) " ~ op ~ "= a"); }
  ModInt opBinaryRight(string op, T)(T a) const { return mixin("ModInt(a) " ~ op ~ "= this"); }
  bool opCast(T: bool)() const { return (x != 0U); }
  string toString() const { return x.to!string; }
}

alias Mint = ModInt;
Mint solve(int p, int e, long L, long R) {
  const m = p^^e;
  Mint.M = m;
  auto fac = new Mint[m];
  fac[0] = 1;
  foreach (i; 1 .. m) {
    fac[i] = fac[i - 1] * ((i % p != 0) ? i : 1);
  }
  auto invFac = new Mint[m];
  invFac[m - 1] = fac[m - 1].inv;
  foreach_reverse (i; 1 .. m) {
    invFac[i - 1] = invFac[i] * ((i % p != 0) ? i : 1);
  }
  Mint binom(long n, long k) {
    const l = n - k;
    Mint ret = 1;
    long sum1, sumE;
    int f;
    for (long nn = n, kk = k, ll = l; nn > 0; nn /= p, kk /= p, ll /= p, ++f) {
      ret *= fac[nn % m] * invFac[kk % m] * invFac[ll % m];
      if (f >= 1) sum1 += (nn - kk - ll);
      if (f >= e) sumE += (nn - kk - ll);
    }
    if (!(p == 2 && e >= 3) && (sum1 & 1)) {
      ret = -ret;
    }
    ret *= p^^(min(sumE, e));
    return ret;
  }
  
  Mint ret;
  foreach (n; L .. R + 1) {
    const res = binom(2 * n, n);
    debug {
      if (R - L <= 10) {
        writefln("binom(%s, %s) == %s (mod %s^%s)", 2 * n, n, res, p, e);
      }
    }
    ret += (res - 2);
  }
  return ret;
}

void main() {
  try {
    for (; ; ) {
      const L = readLong;
      const R = readLong;
      const M = readInt;
      
      int n = 1;
      int ans;
      void doIt(int p, int e) {
        const res = solve(p, e, L, R);
        for (; Mint(ans) != res; ans += n) {}
        n *= Mint.M;
      }
      {
        int m = M;
        for (int p = 2; p * p <= m; ++p) if (m % p == 0) {
          int e;
          do {
            ++e;
            m /= p;
          } while (m % p == 0);
          doIt(p, e);
        }
        if (m > 1) {
          doIt(m, 1);
        }
      }
      
      writeln(ans);
    }
  } catch (EOFException e) {
  }
}