foo.cc: In function 'int main()':
foo.cc:7:14: warning: unused variable 'y' [-Wunused-variable]
  int x,a,b,c,y;
              ^
foo.cc:10:9: warning: 'a' is used uninitialized in this function [-Wuninitialized]
     if(a<b && b<c)
        ~^~
foo.cc:10:9: warning: 'b' is used uninitialized in this function [-Wuninitialized]
foo.cc:10:16: warning: 'c' is used uninitialized in this function [-Wuninitialized]
     if(a<b && b<c)
               ~^~

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