View Compilation Error

0_0_32260237_2620.cpp: In function 'int insert(char*)':
0_0_32260237_2620.cpp:21:32: error: 'strlen' was not declared in this scope
  for (int i = 0; i < strlen(str); i++) {
                                ^
0_0_32260237_2620.cpp: In function 'int main()':
0_0_32260237_2620.cpp:55:34: error: 'memset' was not declared in this scope
    memset(Zheng, 0, sizeof(Zheng));
                                  ^