foo.cc: In function 'int main()':
foo.cc:14:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   14 |     scanf("%d",&n);
      |     ~~~~~^~~~~~~~~
foo.cc:18:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   18 |             scanf("%d",&f[i][j]);
      |             ~~~~~^~~~~~~~~~~~~~~
foo.cc:25:14: warning: 'next' may be used uninitialized in this function [-Wmaybe-uninitialized]
   25 |     while(now!=n){
      |           ~~~^~~

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