foo.cc: In function 'int main()':
foo.cc:6:8: warning: unused variable 's' [-Wunused-variable]
    6 |  int n,s;scanf("%d",&n);
      |        ^
foo.cc:6:15: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    6 |  int n,s;scanf("%d",&n);
      |          ~~~~~^~~~~~~~~
foo.cc:9:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    9 |    scanf("%d",&a[j][i]);
      |    ~~~~~^~~~~~~~~~~~~~~

Found 5 testcases.
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