foo.cc: In function 'pii dfs(int)':
foo.cc:22:11: warning: unused variable 'c1' [-Wunused-variable]
   22 | int s1,s2,c1,c2;
      |           ^~
foo.cc:22:14: warning: unused variable 'c2' [-Wunused-variable]
   22 | int s1,s2,c1,c2;
      |              ^~
foo.cc: In function 'int main()':
foo.cc:58:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   58 | scanf("%d",&n);
      | ~~~~~^~~~~~~~~
foo.cc:62:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   62 | scanf("%d",&price[i]);
      | ~~~~~^~~~~~~~~~~~~~~~

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