Fix redundant copy in convolution

Author: RezwanArefin01

atcoder/convolution.hpp

@@ -223,8 +223,8 @@ std::vector<mint> convolution(std::vector<mint>&& a, std::vector<mint>&& b) {
     int z = (int)internal::bit_ceil((unsigned int)(n + m - 1));
     assert((mint::mod() - 1) % z == 0);
 
-    if (std::min(n, m) <= 60) return convolution_naive(a, b);
-    return internal::convolution_fft(a, b);
+    if (std::min(n, m) <= 60) return convolution_naive(std::move(a), std::move(b));
+    return internal::convolution_fft(std::move(a), std::move(b));
 }
 template <class mint, internal::is_static_modint_t<mint>* = nullptr>
 std::vector<mint> convolution(const std::vector<mint>& a,