foo.cc: In function 'void solve()':
foo.cc:71:14: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   71 |   if(s.size()>=n){
      |      ~~~~~~~~^~~
foo.cc:63:6: warning: unused variable 'len' [-Wunused-variable]
   63 |  int len=0;
      |      ^~~
foo.cc: In function 'int main()':
foo.cc:90:16: warning: unused variable 'num2' [-Wunused-variable]
   90 |     int t = 0, num2 = 0;
      |                ^~~~
foo.cc:101:6: warning: unused variable 'num1' [-Wunused-variable]
  101 |  int num1 = 0;
      |      ^~~~

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