View Compilation Error

0_0_21035538_6875.cpp: In function 'int main()':
0_0_21035538_6875.cpp:112:25: error: 'str' was not declared in this scope
             scanf("%s", str[i]);
                         ^
0_0_21035538_6875.cpp:121:33: error: 'str' was not declared in this scope
         printf("%d\n", ac.query(str[i]));
                                 ^