View Compilation Error

0_0_29540587_9867.cpp: In function 'int spfa(int)':
0_0_29540587_9867.cpp:23:26: error: 'memset' was not declared in this scope
  memset(vis,0,sizeof(vis));
                          ^
0_0_29540587_9867.cpp: In function 'int main()':
0_0_29540587_9867.cpp:54:23: error: 'memset' was not declared in this scope
   memset(p,0,sizeof(p));
                       ^