foo.cc: In function 'int main()':
foo.cc:80:7: warning: variable 'temp' set but not used [-Wunused-but-set-variable]
   80 |  Node temp;
      |       ^~~~
foo.cc:89:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   89 |     scanf("%d",&a[j][k]);
      |     ~~~~~^~~~~~~~~~~~~~~

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