foo.cc: In function 'int main()':
foo.cc:48:5: warning: 'flag' may be used uninitialized in this function [-Wmaybe-uninitialized]
   48 |     if(flag)
      |     ^~
foo.cc:24:29: warning: 'RM' may be used uninitialized in this function [-Wmaybe-uninitialized]
   24 |     double RL=L[N-1]/2,RR=S,RM;
      |                             ^~

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