foo.cc: In function 'int main()':
foo.cc:10:25: warning: unused variable 'b' [-Wunused-variable]
   10 |                 int a=i,b;
      |                         ^
foo.cc:17:15: warning: 's' may be used uninitialized [-Wmaybe-uninitialized]
   17 |         cout<<s;
      |               ^
foo.cc:6:17: note: 's' was declared here
    6 |         int L,R,s;
      |                 ^

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