View Compilation Error

0_0_26615106_28131.cpp: In function 'int spfa(int)':
0_0_26615106_28131.cpp:23:22: error: 'memset' was not declared in this scope
  memset(f,0,sizeof(f));
                      ^
0_0_26615106_28131.cpp: In function 'int main()':
0_0_26615106_28131.cpp:58:28: error: 'memset' was not declared in this scope
   memset(adj,-1,sizeof(adj));
                            ^