/in/foo.c: In function 'unique':
/in/foo.c:5:10: warning: statement with no effect [-Wunused-value]
    5 |          n;
      |          ^
/in/foo.c: In function 'main':
/in/foo.c:24:23: warning: unused variable 's' [-Wunused-variable]
   24 |         int n1, n2, i,s;
      |                       ^