View Compilation Error

0_0_17767076_2098.cpp: In function 'int main(int, char**)':
0_0_17767076_2098.cpp:22:28: error: 'sort' was not declared in this scope
       sort(a, a + n, my_cmp);
                            ^
0_0_17767076_2098.cpp:29:5: error: expected ';' before '}' token
     }
     ^