View Compilation Error

0_0_18847405_11986.cpp: In function 'int main()':
0_0_18847405_11986.cpp:88:32: error: 'memset' was not declared in this scope
    memset(level,0,sizeof(level));
                                ^
0_0_18847405_11986.cpp:101:32: error: 'memset' was not declared in this scope
    memset(level,0,sizeof(level));
                                ^