foo.cc: In function 'int main()':
foo.cc:27:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   27 |  scanf("%d",&T);
      |  ~~~~~^~~~~~~~~
foo.cc:31:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   31 |   scanf("%d%d",&n,&m);
      |   ~~~~~^~~~~~~~~~~~~~
foo.cc:37:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   37 |    scanf("%d%d",&a,&b);
      |    ~~~~~^~~~~~~~~~~~~~
foo.cc:41:36: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   41 |     for(int k=j+1; k<=m; k++) scanf("%d%d",&a,&b);
      |                               ~~~~~^~~~~~~~~~~~~~

Found 10 testcases.
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