foo.cc: In function 'int main()':
foo.cc:14:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 |         for(int i = 0; i < n+s1.size()-2; ++i){
      |                        ~~^~~~~~~~~~~~~~~
foo.cc:15:25: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   15 |                 if(s[i] = s1[0]){
foo.cc:17:54: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   17 |                         while(s[i+j] == s1[j] && j+i < n+s1.size()-2){
      |                                                  ~~~~^~~~~~~~~~~~~~~
foo.cc:20:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   20 |                         if(j == s1.size()){
      |                            ~~^~~~~~~~~~~~
foo.cc:13:13: warning: unused variable 'k' [-Wunused-variable]
   13 |         int k, j = 0, ans = 0;
      |             ^
foo.cc:13:16: warning: unused variable 'j' [-Wunused-variable]
   13 |         int k, j = 0, ans = 0;
      |                ^

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