/in/foo.cc:6:20: error: 'char index [10000][10000]' redeclared as different kind of symbol
 char index[MAX][MAX];
                    ^
In file included from /in/foo.cc:3:0:
/usr/include/string.h:477:1: note: previous declaration 'const char* index(const char*, int)'
 index (const char *__s, int __c) __THROW
 ^~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:16:11: error: invalid types '<unresolved overloaded function type>[int]' for array subscript
    index[k][i] = ' ';
           ^
/in/foo.cc:24:11: error: invalid types '<unresolved overloaded function type>[int]' for array subscript
    index[x][y] = str[i];
           ^
/in/foo.cc:28:11: error: invalid types '<unresolved overloaded function type>[int]' for array subscript
    index[x][y] = str[i];
           ^
/in/foo.cc:35:16: error: invalid types '<unresolved overloaded function type>[int]' for array subscript
    if (index[tx][ty] != ' ')
                ^
/in/foo.cc:36:21: error: invalid types '<unresolved overloaded function type>[int]' for array subscript
     cout << index[tx][ty];
                     ^