foo.cc:6:12: error: '::main' must return 'int'
 void main ()
            ^
foo.cc: In function 'int main()':
foo.cc:28:7: error: 'm' was not declared in this scope
   for(m=0;m<n;m++)
       ^
foo.cc:35:12: error: 'm' was not declared in this scope
  for(int i=m;i+1<n;i=i+1)
            ^

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