foo.cc: In function 'int main()':
foo.cc:22:29: warning: unused variable 'cm' [-Wunused-variable]
  int s,c1,c2,syz1,syz2,sm=0,cm;
                             ^~
foo.cc:44:4: warning: 'b[3]' may be used uninitialized in this function [-Wmaybe-uninitialized]
  c2=b[3]+b[4];
  ~~^~~~~~~~~~
foo.cc:43:4: warning: 'b[2]' may be used uninitialized in this function [-Wmaybe-uninitialized]
  c1=b[1]+b[2];
  ~~^~~~~~~~~~
foo.cc:44:4: warning: 'b[4]' may be used uninitialized in this function [-Wmaybe-uninitialized]
  c2=b[3]+b[4];
  ~~^~~~~~~~~~
foo.cc:47:21: warning: 'b[1]' may be used uninitialized in this function [-Wmaybe-uninitialized]
  if(c1<c2) cout<<b[1]<<b[2];
                     ^

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