foo.cc:13:25: error: stray '\302' in program
   13 |     t = n, n = m, m = t;·
      |                         ^
foo.cc:13:26: error: stray '\267' in program
   13 |     t = n, n = m, m = t;·
      |                          ^
foo.cc: In function 'int main()':
foo.cc:9:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    9 |  scanf ("%lld%lld", &n, &m);
      |  ~~~~~~^~~~~~~~~~~~~~~~~~~~
foo.cc:12:16: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   12 |          scanf ("%lld", &s[j][i]);
      |          ~~~~~~^~~~~~~~~~~~~~~~~~

Found 20 testcases.
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