View Compilation Error

0_0_35553631_1656.cpp: In function 'void init()':
0_0_35553631_1656.cpp:27:31: error: 'memset' was not declared in this scope
  memset(head, -1, sizeof(head));
                               ^
0_0_35553631_1656.cpp: In function 'void dijk(ll)':
0_0_35553631_1656.cpp:38:26: error: 'memset' was not declared in this scope
  memset(d, INF, sizeof(d));
                          ^