foo.cc: In function ‘int main()’:
foo.cc:25:9: warning: ‘n’ is used uninitialized [-Wuninitialized]
   25 |         if (n==c){
      |         ^~
foo.cc:17:17: note: ‘n’ was declared here
   17 |         int a,b,n,c=0;
      |                 ^