foo.cc: In function 'Poly Merge(int, int)':
foo.cc:174:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  174 |   int m = l + r >> 1;
      |           ~~^~~
foo.cc: In instantiation of 'void convolution::poly<mint, g>::init(int) [with mint = convolution::modint::mint<998244353>; int g = 3]':
foo.cc:79:9:   required from 'void convolution::poly<mint, g>::ntt(int, int) [with mint = convolution::modint::mint<998244353>; int g = 3]'
foo.cc:108:9:   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:121:38:   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:151:11:   required from here
foo.cc:69:21: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   69 |         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:41:56:   required from 'convolution::modint::mint<m> convolution::modint::mint<m>::operator+(const convolution::modint::mint<m>&) [with int m = 998244353]'
foo.cc:93:30:   required from 'void convolution::poly<mint, g>::ntt(int, int) [with mint = convolution::modint::mint<998244353>; int g = 3]'
foo.cc:108:9:   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:121:38:   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:151:11:   required from here
foo.cc:37:54: warning: comparison of integer expressions of different signedness: 'unsigned int' and 'const int' [-Wsign-compare]
   37 |     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:42:56:   required from 'convolution::modint::mint<m> convolution::modint::mint<m>::operator-(const convolution::modint::mint<m>&) [with int m = 998244353]'
foo.cc:94:36:   required from 'void convolution::poly<mint, g>::ntt(int, int) [with mint = convolution::modint::mint<998244353>; int g = 3]'
foo.cc:108:9:   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:121:38:   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:151:11:   required from here
foo.cc:38:60: warning: comparison of integer expressions of different signedness: 'unsigned int' and 'const int' [-Wsign-compare]
   38 |     mint& operator-=(const mint& t){ x += mod - t.x; if (x >= mod) x -= mod; return *this; }
      |                                                          ~~^~~~~~
foo.cc: In function 'int main()':
foo.cc:183:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  183 |     scanf("%d",&n);
      |     ~~~~~^~~~~~~~~
foo.cc:186:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  186 |    scanf("%d",&v[j][i]);
      |    ~~~~~^~~~~~~~~~~~~~~

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