foo.cc: In function 'node* insert(node*, int)':
foo.cc:51:15: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   51 |         if (i = head)
      |             ~~^~~~~~
foo.cc: In function 'int main()':
foo.cc:65:16: warning: unused variable 'i' [-Wunused-variable]
   65 |         int n, i, t;
      |                ^
foo.cc:67:30: warning: unused variable 'p' [-Wunused-variable]
   67 |         node* head = NULL, * p = NULL;
      |                              ^

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