View Compilation Error

0_0_35326971_17980.cpp: In function 'void Dijkstra()':
0_0_35326971_17980.cpp:17:31: error: 'memset' was not declared in this scope
     memset(vis, 0, sizeof(vis));
                               ^
0_0_35326971_17980.cpp: In function 'int main()':
0_0_35326971_17980.cpp:65:26: error: 'strcmp' was not declared in this scope
         if (strcmp(st, en) == 0)///用于判断两地是否一样，如果一样就直接输出0
                          ^