foo.cc: In function 'int main()':
foo.cc:12:17: warning: 'i' may be used uninitialized [-Wmaybe-uninitialized]
   12 |         for(int i; i<n-1; i++) if(d[i]>M) M=d[i],Ma=i;
      |                 ^
foo.cc:13:31: warning: 'Ma' may be used uninitialized [-Wmaybe-uninitialized]
   13 |         cout<<a[Ma]<<' '<<a[Ma+1];
      |                             ~~^~
foo.cc:11:17: note: 'Ma' was declared here
   11 |         int M=0,Ma;
      |                 ^~

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