import sys
input = sys.stdin.readline

class BinomialCoefficient:
	def __init__(self, mod):
		self.mod = mod
		self.prime = self.prime_factorize(mod)
		self.facs = []
		self.invs = []
		self.pows = []
		for p, c in self.prime:
			pc = pow(p, c)
			fac = [1] * pc
			inv = [1] * pc
			for i in range(1, pc):
				k = i
				if(i % p == 0):
					k = 1
				fac[i] = fac[i - 1] * k % pc
			inv[-1] = fac[-1]
			for i in range(pc - 1, 0, -1):
				k = i
				if(i % p == 0):
					k = 1
				inv[i - 1] = inv[i] * k % pc
			self.facs.append(fac)
			self.invs.append(inv)
			pw = [1]
			while(pw[-1] * p != pc):
				pw.append(pw[-1] * p)
			self.pows.append(pw)

	def prime_factorize(self, n):
		prime = []
		f = 2
		while(f * f <= n):
			if(n % f == 0):
				n //= f
				cnt = 1
				while(n % f == 0):
					n //= f
					cnt += 1
				prime.append((f, cnt))
			f += 1
		if(n != 1):
			prime.append((n, 1))
		return prime

	def crt(self, r, m):
		n = len(r)
		r0 = 0
		m0 = 1
		for a, b in zip(r, m):
			r1 = a % b
			m1 = b
			if(m0 < m1):
				r0, r1, m0, m1 = r1, r0, m1, m0
			if(m0 % m1 == 0):
				if(r0 % m1 != r1):
					return 0
				continue
			g, im = self.inv_gcd(m0, m1)
			u1 = m1 // g
			if((r1 - r0) % g != 0):
				return 0
			x = (r1 - r0) // g * im % u1
			r0 += x * m0
			m0 *= u1
			if(r0 < 0):
				r0 += m0
		return r0

	def inv_gcd(self, n, m):
		n %= m
		if(n == 0):
			return m, 0
		s, t, m0, m1 = m, n, 0, 1
		while(t):
			u = s // t
			s -= t * u
			m0 -= m1 * u
			m0, m1, s, t = m1, m0, t, s
		if(m0 < 0):
			m0 += m // s
		return s, m0

	def inv_mod(self, n, m):
		g, im = self.inv_gcd(n, m)
		return im

	def calc_e(self, n, k, r, p):
		e = 0
		while(n):
			n //= p
			e += n
		while(k):
			k //= p
			e -= k
		while(r):
			r //= p
			e -= r
		return e

	def lucas(self, n, k, p, c, i):
		pw = self.pows[i]
		fac = self.facs[i]
		inv = self.invs[i]
		r = n - k
		pc = pow(p, c)
		e = self.calc_e(n, k, r, p)
		if(e >= len(pw)):
			return 0
		ret = pw[e]
		if((p != 2 or c < 3) and (self.calc_e(n // pw[-1], k // pw[-1], r // pw[-1], p) & 1)):
			ret *= -1
		while(n):
			ret *= fac[n % pc] * inv[k % pc] * inv[r % pc]
			ret %= pc
			n //= p
			k //= p
			r //= p
		return ret

	def __call__(self, n, k):
		if(k < 0 or k > n):
			return 0
		if(k == 0 or k == n):
			return 1
		r = []
		m = []
		for i, (p, c) in enumerate(self.prime):
			r.append(self.lucas(n, k, p, c, i))
			m.append(pow(p, c))
		return self.crt(r, m)


"""
Main Code
"""

l, r, m = map(int, input().split())

nCk = BinomialCoefficient(m)
ans = 0
for i in range(l, r + 1):
	ans += nCk(2 * i, i) + m - 2
	ans %= m
print(ans)