View Compilation Error

0_0_20970322_28528.cpp: In function 'void init()':
0_0_20970322_28528.cpp:12:36: error: 'memset' was not declared in this scope
 #define mset(a) memset(a,0,sizeof a)  
                                    ^
0_0_20970322_28528.cpp:20:5: note: in expansion of macro 'mset'
     mset(num);  
     ^
0_0_20970322_28528.cpp: In function 'void DP()':
0_0_20970322_28528.cpp:12:36: error: 'memset' was not declared in this scope
 #define mset(a) memset(a,0,sizeof a)  
                                    ^
0_0_20970322_28528.cpp:30:5: note: in expansion of macro 'mset'
     mset(dp);  
     ^