foo.cc: In function 'int main()':
foo.cc:10:17: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   10 |         if (n==1&&m>2||m==1&&n>2)printf("-1\n");
      |             ~~~~^~~~~
foo.cc:6:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    6 |     scanf("%d",&t);
      |     ~~~~~^~~~~~~~~
foo.cc:9:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    9 |         scanf("%d%d",&n,&m);
      |         ~~~~~^~~~~~~~~~~~~~

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