Main.cpp: In function ‘int main()’:
Main.cpp:10:14: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   10 |         scanf("%lld",&T);
      |         ~~~~~^~~~~~~~~~~
Main.cpp:18:22: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   18 |                 scanf("%lld%lld%lld",&a,&b,&c);
      |                 ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

这样的warning是什么错误？

好几道都这样