foo.cc: In function 'int main()':
foo.cc:7:12: warning: unused variable 'j' [-Wunused-variable]
    7 |  int n,s,i,j;
      |            ^
foo.cc:17:2: warning: 's' may be used uninitialized in this function [-Wmaybe-uninitialized]
   17 |  if(s==n)
      |  ^~

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