View Compilation Error

0_0_24798562_17818.cpp: In function 'long long int sap()':
0_0_24798562_17818.cpp:41:29: error: 'memset' was not declared in this scope
  memset(dis, -1, sizeof(dis));
                             ^
0_0_24798562_17818.cpp: In function 'int main()':
0_0_24798562_17818.cpp:174:33: error: 'memset' was not declared in this scope
   memset(first, 0, sizeof(first));
                                 ^