foo.c: In function 'main':
foo.c:6:1: warning: 'n' is used uninitialized in this function [-Wuninitialized]
    6 | int a[n];
      | ^~~
foo.c:7:12: warning: 'm' is used uninitialized in this function [-Wuninitialized]
    7 | for(i=0;i<n-m;i++)a[i]=a[i+m];
      |           ~^~

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