foo.cc:14:13: error: 'int index [20]' redeclared as different kind of entity
   14 | int index[20],pos=0;
      |             ^
In file included from /usr/include/string.h:432,
                 from /usr/include/c++/9/cstring:42,
                 from foo.cc:6:
/usr/include/strings.h:61:1: note: previous declaration 'const char* index(const char*, int)'
   61 | index (const char *__s, int __c) __THROW
      | ^~~~~
foo.cc: In function 'void dfs(int)':
foo.cc:29:18: error: invalid types '<unresolved overloaded function type>[int]' for array subscript
   29 |   if(!vis[index[i]]) continue;
      |                  ^
foo.cc:34:22: error: invalid types '<unresolved overloaded function type>[int]' for array subscript
   34 |     if((a[j]>>index[i])&1)
      |                      ^
foo.cc:42:14: error: invalid types '<unresolved overloaded function type>[int]' for array subscript
   42 |   vis[index[i]]=0;
      |              ^
foo.cc:50:14: error: invalid types '<unresolved overloaded function type>[int]' for array subscript
   50 |   vis[index[i]]=1;
      |              ^
foo.cc: In function 'int main()':
foo.cc:76:50: error: invalid types '<unresolved overloaded function type>[int]' for array subscript
   76 |   if(((a[1]>>i)&1)==0&&((temp>>i)&1)) index[++pos]=i;
      |                                                  ^
foo.cc:68:8: warning: unused variable 'y' [-Wunused-variable]
   68 |  int x,y;
      |        ^
foo.cc:57:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   57 |  scanf("%d%d",&n,&g);
      |  ~~~~~^~~~~~~~~~~~~~
foo.cc:61:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   61 |   scanf("%s",c);
      |   ~~~~~^~~~~~~~

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