foo.cc: In function 'int main()':
foo.cc:22:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   22 |                 for(int j=0;j<st.size();j++)
      |                             ~^~~~~~~~~~
foo.cc:24:32: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |                         while(j<st.size()&&!(st[j]>='0'&&st[j]<='9'))a[i].n+=st[j],j++;
      |                               ~^~~~~~~~~~
foo.cc:25:32: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   25 |                         while(j<st.size())a[i].y=a[i].y*10+st[j]-'0',j++;
      |                               ~^~~~~~~~~~

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