/in/foo.cc: In function 'int main()':
/in/foo.cc:8:9: warning: 'i' may be used uninitialized [-Wmaybe-uninitialized]
    8 |         for(;i<=n;i++)
      |         ^~~
/in/foo.cc:5:15: note: 'i' was declared here
    5 |         int n,i;
      |               ^