foo.cc: In function 'int main()':
foo.cc:13:26: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
   13 |         for(int j = 0; j < strlen(s); ++j){
      |                        ~~^~~~~~~~~~~
foo.cc:10:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   10 |     scanf("%d%d", &L, &R);
      |     ~~~~~^~~~~~~~~~~~~~~~

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