foo.cc: In function 'int FindMaxIndex(int*, int)':
foo.cc:7:17: warning: 'index' is used uninitialized [-Wuninitialized]
    7 |         for(int i=index+1;i<n;i++)
      |                 ^
foo.cc:6:22: note: 'index' was declared here
    6 |         int max=a[0],index;
      |                      ^~~~~

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