View Compilation Error

0_0_21065526_30068.cpp: In function 'void init()':
0_0_21065526_30068.cpp:265:37: error: 'memset' was not declared in this scope
 #define ms(a,b) memset(a,b,sizeof(a))
                                     ^
0_0_21065526_30068.cpp:320:2: note: in expansion of macro 'ms'
  ms(index, -1);
  ^