View Compilation Error

0_0_21750352_10814.cpp: In function 'void bfs(int)':
0_0_21750352_10814.cpp:26:36: error: 'memset' was not declared in this scope
     memset(level, -1, sizeof(level));
                                    ^
0_0_21750352_10814.cpp: In function 'LL max_flow(int, int)':
0_0_21750352_10814.cpp:77:37: error: 'memset' was not declared in this scope
         memset(iter, 0, sizeof(iter));
                                     ^