foo.cc: In function 'void pluss()':
foo.cc:21:35: warning: iteration 8 invokes undefined behavior [-Waggressive-loop-optimizations]
   21 |     for(int i=1;i<=9;i++){c[i]=a[i]+b[i];}//加法
      |                                ~~~^
foo.cc:21:18: note: within this loop
   21 |     for(int i=1;i<=9;i++){c[i]=a[i]+b[i];}//加法
      |                 ~^~~

Found 5 testcases.
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