foo.cc: In function 'int main()':
foo.cc:139:18: warning: unused variable 'k' [-Wunused-variable]
  139 |     int n, i, j, k;
      |                  ^
foo.cc: In instantiation of 'void convolution::poly<mint, g>::init(int) [with mint = convolution::modint::mint<998244353>; int g = 3]':
foo.cc:72:13:   required from 'void convolution::poly<mint, g>::ntt(int, int) [with mint = convolution::modint::mint<998244353>; int g = 3]'
foo.cc:101:13:   required from 'convolution::poly<mint, g> convolution::poly<mint, g>::convolution_ntt(convolution::poly<mint, g>) [with mint = convolution::modint::mint<998244353>; int g = 3]'
foo.cc:114:43:   required from 'convolution::poly<mint, g>& convolution::poly<mint, g>::operator*=(const convolution::poly<mint, g>&) [with mint = convolution::modint::mint<998244353>; int g = 3]'
foo.cc:115:60:   required from 'convolution::poly<mint, g> convolution::poly<mint, g>::operator*(const convolution::poly<mint, g>&) [with mint = convolution::modint::mint<998244353>; int g = 3]'
foo.cc:153:21:   required from here
foo.cc:62:26: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   62 |             if (r.size() < limit) r.resize(limit);
      |                 ~~~~~~~~~^~~~~~~
foo.cc: In instantiation of 'convolution::modint::mint<m>& convolution::modint::mint<m>::operator+=(const convolution::modint::mint<m>&) [with int m = 998244353]':
foo.cc:34:64:   required from 'convolution::modint::mint<m> convolution::modint::mint<m>::operator+(const convolution::modint::mint<m>&) [with int m = 998244353]'
foo.cc:86:34:   required from 'void convolution::poly<mint, g>::ntt(int, int) [with mint = convolution::modint::mint<998244353>; int g = 3]'
foo.cc:101:13:   required from 'convolution::poly<mint, g> convolution::poly<mint, g>::convolution_ntt(convolution::poly<mint, g>) [with mint = convolution::modint::mint<998244353>; int g = 3]'
foo.cc:114:43:   required from 'convolution::poly<mint, g>& convolution::poly<mint, g>::operator*=(const convolution::poly<mint, g>&) [with mint = convolution::modint::mint<998244353>; int g = 3]'
foo.cc:115:60:   required from 'convolution::poly<mint, g> convolution::poly<mint, g>::operator*(const convolution::poly<mint, g>&) [with mint = convolution::modint::mint<998244353>; int g = 3]'
foo.cc:153:21:   required from here
foo.cc:30:63: warning: comparison of integer expressions of different signedness: 'unsigned int' and 'const int' [-Wsign-compare]
   30 |             mint& operator+=(const mint& t) { x += t.x; if (x >= mod) x -= mod; return *this; }
      |                                                             ~~^~~~~~
foo.cc: In instantiation of 'convolution::modint::mint<m>& convolution::modint::mint<m>::operator-=(const convolution::modint::mint<m>&) [with int m = 998244353]':
foo.cc:35:64:   required from 'convolution::modint::mint<m> convolution::modint::mint<m>::operator-(const convolution::modint::mint<m>&) [with int m = 998244353]'
foo.cc:87:40:   required from 'void convolution::poly<mint, g>::ntt(int, int) [with mint = convolution::modint::mint<998244353>; int g = 3]'
foo.cc:101:13:   required from 'convolution::poly<mint, g> convolution::poly<mint, g>::convolution_ntt(convolution::poly<mint, g>) [with mint = convolution::modint::mint<998244353>; int g = 3]'
foo.cc:114:43:   required from 'convolution::poly<mint, g>& convolution::poly<mint, g>::operator*=(const convolution::poly<mint, g>&) [with mint = convolution::modint::mint<998244353>; int g = 3]'
foo.cc:115:60:   required from 'convolution::poly<mint, g> convolution::poly<mint, g>::operator*(const convolution::poly<mint, g>&) [with mint = convolution::modint::mint<998244353>; int g = 3]'
foo.cc:153:21:   required from here
foo.cc:31:69: warning: comparison of integer expressions of different signedness: 'unsigned int' and 'const int' [-Wsign-compare]
   31 |             mint& operator-=(const mint& t) { x += mod - t.x; if (x >= mod) x -= mod; return *this; }
      |                                                                   ~~^~~~~~

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