foo.cc: In function 'int main()':
foo.cc:5:17: warning: 'a' is used uninitialized in this function [-Wuninitialized]
  int a,b,c,n=100*a+10*b+c;
              ~~~^~
foo.cc:5:22: warning: 'b' is used uninitialized in this function [-Wuninitialized]
  int a,b,c,n=100*a+10*b+c;
                    ~~^~
foo.cc:5:24: warning: 'c' is used uninitialized in this function [-Wuninitialized]
  int a,b,c,n=100*a+10*b+c;
              ~~~~~~~~~~^~

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