foo.cc: In function 'int main()':
foo.cc:18:11: warning: pointer to a function used in arithmetic [-Wpointer-arith]
   18 |  cout<<gcd+1;
      |        ~~~^~
foo.cc:12:8: warning: unused variable 'm' [-Wunused-variable]
   12 |  int c,m,n,a[100];
      |        ^
foo.cc:12:10: warning: unused variable 'n' [-Wunused-variable]
   12 |  int c,m,n,a[100];
      |          ^

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