Created
September 24, 2018 14:12
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AtCoder ABC #110 D
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require 'prime' | |
MAX = 10**6 | |
MOD = 10**9 + 7 | |
@fac = [] | |
@faci = [] | |
@inv = [] | |
@fac[0] = @fac[1] = 1 | |
@faci[0] = @faci[1] = 1 | |
@inv[1] = 1 | |
2.upto(MAX) do |i| | |
@fac[i] = @fac[i - 1] * i % MOD | |
@inv[i] = MOD - @inv[MOD % i] * (MOD / i) % MOD | |
@faci[i] = @faci[i - 1] * @inv[i] % MOD | |
end | |
def comb(n, k) | |
return 0 if n < k | |
return 0 if n < 0 || k < 0 | |
return @fac[n] * (@faci[k] * @faci[n - k] % MOD) % MOD | |
end | |
n, m = gets.chomp.split(" ").map(&:to_i) | |
pmd = Prime.prime_division(m) | |
ans = 1 | |
pmd.each do |pm, e| | |
ans *= comb(e + n - 1, e) | |
ans %= MOD | |
end | |
puts ans |
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