foo.cc: In function 'int main()':
foo.cc:36:10: error: expected unqualified-id before '=' token
  for(int =0;i<n;i++)
          ^
foo.cc:36:10: error: expected ';' before '=' token
foo.cc:36:10: error: expected primary-expression before '=' token
foo.cc:36:13: error: 'i' was not declared in this scope
  for(int =0;i<n;i++)
             ^
foo.cc:36:16: error: expected ')' before ';' token
  for(int =0;i<n;i++)
                ^
foo.cc:36:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for(int =0;i<n;i++)
  ^~~
foo.cc:36:17: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
  for(int =0;i<n;i++)
                 ^
foo.cc:36:17: error: 'i' was not declared in this scope
foo.cc:34:10: warning: unused variable 'n1' [-Wunused-variable]
  int num,n1,n2,L,k,n;
          ^~

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