foo.cc: In function 'int main()':
foo.cc:19:38: warning: variable 'idi' set but not used [-Wunused-but-set-variable]
   19 |    int max=list[i][0],min=list[0][j],idi,idj;
      |                                      ^~~
foo.cc:19:42: warning: variable 'idj' set but not used [-Wunused-but-set-variable]
   19 |    int max=list[i][0],min=list[0][j],idi,idj;
      |                                          ^~~
foo.cc:6:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    6 |  scanf("%d",&n);
      |  ~~~~~^~~~~~~~~

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