View Compilation Error

0_0_21458502_27447.cpp: In function 'void init()':
0_0_21458502_27447.cpp:53:36: error: 'memset' was not declared in this scope
     memset(ans,0, sizeof(int)*(N+1));
                                    ^
0_0_21458502_27447.cpp: In function 'bool Perfect_Match()':
0_0_21458502_27447.cpp:73:38: error: 'memset' was not declared in this scope
     memset(result,0,sizeof(int)*(N+1));
                                      ^
0_0_21458502_27447.cpp: In function 'bool check(int)':
0_0_21458502_27447.cpp:92:40: error: 'memset' was not declared in this scope
     memset(state, 0, sizeof(bool)*(N+1)); 
                                        ^