foo.cc: In function 'int main()':
foo.cc:5:19: warning: 'a' is used uninitialized [-Wuninitialized]
    5 |         string b[a],e[a],f[a];
      |                   ^
foo.cc:4:13: note: 'a' declared here
    4 |         int a,i=1,sum=0,max=0,j;
      |             ^
foo.cc:4:31: warning: 'j' may be used uninitialized in this function [-Wmaybe-uninitialized]
    4 |         int a,i=1,sum=0,max=0,j;
      |                               ^

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