foo.cc: In function 'int main()':
foo.cc:7:22: warning: left operand of comma operator has no effect [-Wunused-value]
    7 |         for(int i=1;i<7,i++)
      |                     ~^~
foo.cc:7:28: error: expected ';' before ')' token
    7 |         for(int i=1;i<7,i++)
      |                            ^
      |                            ;
foo.cc:13:21: error: invalid types 'int[int]' for array subscript
   13 |                 if(a[c]<a[i]) c=i;
      |                     ^
foo.cc:13:26: error: invalid types 'int[int]' for array subscript
   13 |                 if(a[c]<a[i]) c=i;
      |                          ^

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