View Compilation Error

0_0_38369053_17139.cpp: In function 'void solve()':
0_0_38369053_17139.cpp:17:20: error: 'gcd' is not a member of 'std'
             res += std::gcd(i & j, i | j);
                    ^
0_0_38369053_17139.cpp:17:20: note: suggested alternative:
0_0_38369053_17139.cpp:6:5: note:   'gcd'
 int gcd(int x, int y) {
     ^