foo.cc: In function 'void Main()':
foo.cc:27:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
 scanf("%d%d",&n,&MOD);n-=3;
 ~~~~~^~~~~~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:74:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
 scanf("%d",&T);
 ~~~~~^~~~~~~~~

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